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Shoreline StructuresEnvironmental

Design

A Guide for Structuresalong Estuaries andLarge Rivers

The Stewardship Series

NATIONAL LIBRARY OF CANADA CATALOGUING INPUBLICATION DATA

Adams, Mark A.

Shoreline structures environmental design : a guide for structuresalong estuaries and large rivers

(The Stewardship Series)

“This manual is a publication of the Habitat and Enhancement Branch ofFisheries and Oceans Canada and the Canadian Wildlife Service ofEnvironment Canada.”—p.3.Includes bibliographical references.Issued also in print format.Mode of access : WWW site of Environment Canada.ISBN 0-662-33045-5Cat. no. En4-7/2002E-IN

1. Shorelines – Environmental aspects – British Columbia.2. Waterfronts – Environmental aspects – British Columbia.3. Estuarine area conservation – Environmental aspects – British Columbia.4. Coastal zone management – British Columbia.5. Habitat conservation – British Columbia.I. Canada. Environment Canada.II. Fisheries and Oceans Canada. Habitat and Enhancement Branch.III. Canadian Wildlife Service.IV. Title.V. Series: Stewardship series.

GB460.C3A32 2003 333.91’7’09711 C2003-980100-4

ACKNOWLEDGEMENTS

Funding for this publication was provided by Fisheries andOceans Canada and Environment Canada

Project AdministratorsOtto E. Langer, Fisheries and Oceans CanadaDave Harper, Fisheries and Oceans Canada

Project Manager and AuthorMark A. Adams, ECL Envirowest Consultants Limited

Technical Editors and ContributorsGary L. Williams, G.L. Williams and Associates Ltd.Peter Morgan, Hay and Company Consultants Inc.

Graphic Design and LayoutKaren E. Asp, ECL Envirowest Consultants LimitedMark A. Adams, ECL Envirowest Consultants Limited

Graphic TechnicianMichael G. Macfarlane, ECL Envirowest Consultants Limited

IllustrationsCover: Karen E. Asp, ECL Envirowest Consultants LimitedChapters: Pete Willows, ECL Envirowest Consultants Limited

Photographs are Reproduced with Permission fromMark A. Adams, ECL Envirowest Consultants LimitedScott Barrett, BC Ministry of Water, Land and Air ProtectionEric D. Beaubien, ECL Envirowest Consultants LimitedR. Wayne Campbell, Wayne Campbell and AssociatesCanadian Wildlife ServiceRobert Cochrane, ECL Envirowest Consultants LimitedJohn M. Cooper, Manning, Cooper and AssociatesFraser River Port AuthorityJohn Grindon, Brinkman & Associates Reforestation Ltd.Rick Harbo, Fisheries and Oceans CanadaMyles Hargrove, Shady Creek Native Plants and EnvironmentalContracting Ltd.Kon Johansen, Fisheries and Oceans CanadaRachael E. Jones, ECL Envirowest Consultants LimitedOtto. E Langer, Fisheries and Oceans CanadaArt McLeod, Exceptional PhotographyBruce Peel, Peel’s Nurseries Ltd.Province of British ColumbiaRolf W. Sickmuller, ECL Envirowest Consultants LimitedGary L. Williams, G.L. Williams and Associates Ltd.

PUBLICATION CITATION

Adams , M.A. 2002 . Shore l ine S t ruc ture s Env i ronmenta lDesign: A Guide For Structures Along Estuaries and LargeRivers . Fi sher ie s and Oceans Canada , Vancouver, BC andEnvironment Canada, Delta, BC. 68p + appendices.

iii

Contents

Preface ................................................................................................................................................... i v

Chapter 1 - Shoreline Environments1.1 Shoreline Environments ..................................................................................................... 11.2 Purpose............................................................................................................................. 31.3 Scope................................................................................................................................ 31.4 Content Overview ............................................................................................................... 3

Chapter 2 - Habitat Structure and Function2.1 Introduction ....................................................................................................................... 52.2 Tidal Flats ......................................................................................................................... 62.3 Eelgrass Meadows ............................................................................................................ 92.4 Tidal Marshes ................................................................................................................... 112.5 Riparian Woodlands .........................................................................................................13

Chapter 3 - Legislation and the Project Review Process3.1 Introduction ......................................................................................................................173.2 Fisheries and Oceans Canada and the Fisheries Act ...................................................... 173.3 Other Authorities and Acts of Legislation ......................................................................... 23

Chapter 4 - Facilities and Structures4.1 Introduction ......................................................................................................................294.2 Description of Structures ..................................................................................................294.3 Environmental Design Parameters ....................................................................................32

Chapter 5 - Dikes5.1 Introduction ......................................................................................................................415.2 Structural Design Criteria ..................................................................................................425.3 Environmental Design .......................................................................................................445.4 Maintenance .....................................................................................................................48

Chapter 6 - Establishing Vegetation6.1 Introduction ......................................................................................................................536.2 Site Preparation................................................................................................................536.3 Species Selection ............................................................................................................566.4 Plant Propagules and Planting..........................................................................................596.5 Maintenance .....................................................................................................................68

Appendix A - Glossary

Appendix B - Bibliography and Photographic Credits

Appendix C - Common Wetland and Riparian Plants

iv

Shoreline Structures Environmental Design – A Guide for Structures alongEstuaries and Large Rivers is a product of the Fraser River Action Plan, aninitiative of Canada’s Green Plan. The Fraser River Action Plan encouragedpartnerships between government and non-government stewards of theenvironment, facilitated pollution reduction and clean up, and promoted betterscience to make the Fraser River a healthier environment.

This guide was designed as a Stewardship Series publication. It is somewhatdifferent from the other publications in the series in that, in addition to planningand management guidance, this guide also provides detailed environmental designconcepts. Its target audience is the same as the other Stewardship Seriespublications; local governments, land owners, developers and communitystewardship groups can all benefit from understanding and adopting the designprinciples outlined in this guide.

The environmental design concepts presented in this publication will helpproponents to mitigate the negative impacts that shoreline developments can haveon fish and wildlife habitats. This guide will also help the proponent to recognizethat shoreline environments are composed of many interdependent biological andphysical components and that impacts to any one component will have a decidedeffect on others.

The lower Fraser River and its estuary were the original focus of this guide;however, during its development, it became apparent that many of theenvironmentally friendly design concepts presented in this guide would be generallyapplicable to any large river or estuary. Thus, despite the numerous references to theFraser River and its estuary, the guide can be applied to shoreline projects withinlarge rivers and estuaries throughout coastal British Columbia.

This guide would not have been possible without the collaborative effort of stafffrom Fisheries and Oceans Canada, Environment Canada (Canadian WildlifeService), North Fraser Port Authority, Fraser Port Authority, and the B.C. Ministryof Water, Land and Air Protection. Their contributions are greatly appreciated.

Preface

1

1Introduction

1.1 Shoreline Environments

British Columbia’s coast is a composite of numerous shorelineenvironments that support important habitats for fish andwildlife. Estuaries and the lower reaches of large rivers are twoof the more conspicuous of these environments.

An estuary may be defined as a semi-enclosed body of waterwith an open connection to the ocean, where at its seawardmargin seawater is measurably diluted by fresh water from landdrainage, and at its landward margin water levels are measurablyaltered by tides.

Estuaries often occur within sheltered bays, inlets and coves.These sheltered environments reduce mixing of fresh and saltwaters, and in combination with seasonal variations in fresh waterdischarge and the daily fluctuation of tides, create distinct zonesof salinity from the mouth of the stream or river to the openocean. Large quantities of sediment are discharged into estuariesby larger streams and rivers, creating physically complex anddynamic deltas. Fluctuations in water levels, attributable toseasonal variations in discharge and tides, add to the complexand dynamic nature of estuaries. The transitional environmentscreated by distinct zones of salinity, fluctuating water levels andthe deposition of sediments sustain important shoreline habitatsfor a rich assemblage of fish and wildlife species.

The lower reaches of r ivers often share many physicalcharacteristics with estuaries. Seasonal variations in dischargeresult in concurrent fluctuations in water levels. The depositionof sediments creates a complex of floodplain features. Islands,bars and flood channels are features common to both riverinefloodplains and estuarine deltas. The shorelines of estuaries andthe lower reaches of large rivers form a large contiguous corridorthat is utilized by many fish and wildlife species.

Shoreline Structures Environmental DesignPage 2

Figure 1.1 The conversion of natural shorelines to developed areas has resulted in a considerable loss of fish andwildlife habitat (Ladner Channel, Main Arm distributary channel, Fraser River).

1963

1992

Estuaries and the lower reaches of rivers arecharacterized by low grades and fertile soils.These character ist ics , together with thesheltered nature of these coastal features, renderestuaries and the lower reaches of rivers idealloca t ions for human ac t iv i t i e s . Thedevelopment of natural shorelines to supportagricultural, urban and industrial uses has oftenresulted in a substantial loss of fish and wildlifehabitat over time (Figure 1.1).

Historically, the development of naturalshore l ines occurred wi thout e f f ec t ivemitigation of impacts to fish and wildlifehabitats. Only since the mid-1980’s have

shoreline development projects incorporatedenvironmental design criteria that effectivelymit igate impacts . Fi sher ies and OceansCanada’s “Policy for the Management of FishHabitat” (1986) was instrumental in guidingthis change in design approach. Effectivehab i ta t conserva t ion po l i c i e s o f o therregulatory agencies, such as the CanadianWildlife Service of Environment Canada,implemented independently or in collaborationwith Fisheries and Oceans Canada’s habitatpolicy, have also substantially reduced theimpacts of shoreline development projectsupon fish and wildlife habitats.

Chapter 1 - Introduction Page 3

Environmental design criteria that effectivelymitigate impacts to habitats have not beenread i ly acce s s ib l e to proponents o fdevelopment. Basic environmental designcriteria should be readily accessible to allindividuals involved in the planning and designof shoreline projects. Accessibility promotesthe application of these criteria and, in turn,the conservation and protection of shorelineenvironments.

1.2 Purpose

The Shoreline Structures EnvironmentalDesign manual was specifically developed toconsolidate and present basic environmentaldesign cr i ter ia for developments withinshoreline environments and assist proponentsto understand how these criteria can be utilizedto conserve and protect fish and wildlifehabitats.

1.3 Scope

The Shoreline Structures EnvironmentalDesign manual provides basic environmentalcriteria for planning and designing shorelinedevelopment projects. As the character ofprojects and shoreline environments variesgreatly, the manual is not a stand-alonedocument. Site-specific investigation andconsultation with environmental agencypersonnel will be required to properly assessproject feasibility.

Although many of the criteria presented in thismanual are useful for shoreline developmentprojects, they are not to be construed as rulesthat must be rigidly adhered to by projectplanners and designers. Every project is uniquein its design constraints and opportunities.Cons iderat ion of these constra ints andopportunities has lead to innovations inproject design that have advanced mitigationtechnology. The criteria presented in thisdocument are intended to assist, not hinder,the development and evolution of innovativemitigation design.

This manual is a publication of the Habitatand Enhancement Branch of Fisheries andOceans Canada and the Canadian WildlifeService of Environment Canada. Accordingly,the manual presents design criteria thatfacilitate the conservation of fish and wildlifehabitats. In some instances, these criteria maynot be consistent with design criteria endorsedand promoted by other regulatory agencies.Consultation with all agencies that haveregulatory authority with respect to the project,including Fisheries and Oceans Canada andEnvironment Canada, wi l l typica l ly berequired to achieve a comprehensive design thatadequate ly addres se s a l l r egu la toryrequirements.

1.4 Content Overview

The Shoreline Structures EnvironmentalDesign manual is comprised of six chapters andthree appendices. Each chapter is capable ofbeing a stand-alone reference on the subjectmatter presented. As such, each chapter maybe amended, as required, independent of theother chapters. The manual is bound to allowthe ready replacement of amended chapters.However, the manual is of greatest use whenall chapters are considered collectively duringthe planning and design of a project.

Chapter 1 ‘Introduction’ introduces the readerto the environmental setting and values ofestuaries and large rivers. It introduces thepurpose of the manual, specifically to providebasic environmental design criteria for projectsthat have the potential to impact shoreline fishand wildlife habitats.

Chapter 2 ‘Habitat Structure and Function’examines the relationship between structure ofconspicuous shoreline environments andassociated fish and wildlife habitat functions.Subsequent chapters elaborate further uponth i s r e l a t ionsh ip a s des ign c r i t e r i a a represented.

Chapter 3 ‘Legislation and the ProjectReview Process’ identifies the main regulatoryagencies and their respect ive legis lat ive


mandate s a s they apply to shore l inedevelopment. Design impact mitigation andcompensation is defined and explained. Aconvent iona l pro jec t r ev iew proces s i sdesc r ibed , wi th spec ia l r e f e rence toAuthorizations pursuant to Subsection 35(2)of the Federal Fisheries Act.

Chapter 4 ‘Facilities and Structures’ presentsdesign criteria intended to mitigate impacts ofshoreline facilities and structures on fish andwildl i fe habitats . Information regardingstructure, location and configuration, andmaterial types is presented.

Chapter 5 ‘Dikes’ presents environmentaldesign criteria for dike design that do notdetract from the dike’s primary function offlood protection.

Chapter 6 ‘Es tab l i sh ing Vegeta t ion’emphasizes a design philosophy that seeks tocreate the best environment possible forestablishing vegetation as a component ofproductive fish and wildlife habitat. Sitepreparation, species and stock types arepresented.

Appendix A ‘Glossary’ provides detaileddefinitions of technical terms presented by thismanual.

Appendix B ‘Bibliography and PhotographicCredits’ acknowledges sources of informationutilized by this manual. Cited and generalsources are referenced. Credits are afforded tothose individuals and organizations that havegranted permis s ion to reproduce the i rphotographs in this publication.

Appendix C ‘Common Wetland and RiparianPlants’ familiarizes the reader with commonwetland and riparian plant species often usedin impact mitigat ion and compensationhabitat projects.

5

2Habitat Structure

and Function

2.1 Introduction

Habitat may be defined as an environment an organism utilizesfor all or part of its life. Obvious habitats are those directlyutilized by organisms, such as shrub woodland used for nestingby birds, or tidal channels explored by fish for food. Anenvironment, however, need not be directly utilized by anorganism to be habitat.

The instream environment is obvious habitat for juvenilesalmonids. The riparian environment, comprised of the uplandarea in immediate proximity to the stream channel, althoughless obvious, is also habitat. Vegetation within the riparianenvironment assists in the regulation of stream temperaturethrough shading and thermal insulation. It deposits organicmatter into the stream channel that is scavenged by detritus-eating insects that are in turn preyed upon by salmonids.Vegetation facilitates a stable flow regime by regulating thedelivery of surface and subsurface drainage into the stream.Both the stream and riparian environments are habitat forjuvenile salmonids.

Structure is an important component of habitat. In essence,structure is the arrangement of physical elements in space.Natural structure is characterized by primary and secondaryphysical elements. Examples of primary elements includetopography and bathymetr y, minera l so i l t ex ture andstratification, seasonal and tidal fluctuations in water levels,and water currents and waves. Secondary physical elements arethose attributable to plants and animals. Examples of secondaryelements include peat soil within sedge marshes, canopy layeringwithin riparian woodlands, and ponding caused by beavers. Thecomplexity of structure is dependent upon the presence andinteraction of these elements.


Shorel ine environments support habitatfunct ions important to the v igour andsurvival of organisms. A function is theinteraction between an organism and itsenvironment. When young waterfowl hidewithin marsh vegetation to escape a predator,the function provided by the vegetation isrefuge. The vegetation does not provide afunction unless the waterfowl use it. Such isthe scenario for al l organisms and theirenvironments; the ability of an environmentto sustain a function, and be habitat, isdependent upon the ability of an organismto use that environment.

Structure is a strong determinant of the typeand number of habitat functions that can besustained by an environment. In general, ifthe complexity of structure is increased, thenumber of functions that can be sustained byan environment is also increased.

The fo l l ow ing s e c t ion s examine ther e l a t i on sh ip be tween the s t ruc tu r e o fconspicuous shoreline environments andassociated fish and wildlife habitat functions.

2.2 Tidal Flats

Tidal f l a t s occur throughout the lowerestuary. They are conspicuous features of thede l t a f ront (Figure 2 .1 ) . Fl a t s may becomposed of clays, muds, sands, gravels orcobbles. Often a flat is composed of severalintergrading zones of substrates.

Different types of substrates provide differentstructural environments for organisms. Eachsubstrate type is characterized by a distinctassemblage of organisms that live within andupon the surface of the sediments (Figure 2.2).The species composition of the assemblage isfurther influenced by the prevailing salinityand tidal regimes.

A notable characteristic of flats is the generalabsence of vascular plant species. Eelgrass(Zostera marina) often occurs along thewaterward margin of tidal flats, at and about

local low water. Intertidal marsh typicallyoccurs along the landward margin of flats.

Non-vascular p lants are of ten commoninhabitants of tidal flats. Unicellular andfilamentous algae often occur within freshand low salinity-brackish flats. High salinity-brackish and salt flats, when large gravels andcobbles are available as anchors, often displayrockweed (Fucus distichus) and sea lettuce(Ulva spp.). The presence of algae enhancesthe structural complexity of tidal flats.

A constant theme for all estuarine tidal flatsis that they receive, to varying degrees, acons tant ‘ r a in’ o f de t r i tu s . Det r i tu s i scomprised of decomposing animal and plantmatter and the bacteria and fungi that inhabitand feed upon it. Detritus is the foundationof the food web of estuarine ecosystems. Themajority of the tidal flat organisms, both interms of number of species and number ofindividuals, consume detritus.

The availability of detritus to deposit andfilter feeders is dependent upon the type ofsubstrates that comprise the f lat . Thesesubstrates are, in turn, dependent upon theprevailing sedimentation regime. Within lowenergy environments, where fine substrates(e.g. clays, muds and fine sands) settle andare retained, detritus comprises a significantfraction of surficial sediments. It is looselyconsolidated and readily suspended within the

Figure 2.1 Tidal flats of Boundary Bay, FraserRiver estuary.

Chapter 2 - Habitat Structure and Function Page 7

Figure 2.2 Generalized brackish tidal flat assemblages of organisms according to substrate type.

a. bent nose clam (Macoma nasuta); b. spionid worm (Spionidae); c. Baltic clam (Macoma balthica);d. mud shrimp (Upogebia pugettensis); e. lugworm (Abarenicola pacifica); f. soft shell clam (Myaarenaria); g. capitellid worm (Capitellidae)

Mud

b.

a.

c.

d.

e.

f.

g.

a. screw shell (Batillaria attramentaria); b. corophid amphipod (Corophium spp.); c. cockle(Clinocardium nuttalli); d. proboscis worm (Glycera spp.); e. butter clam (Saxidomus giganteus);f. littleneck clam (Protothaca staminea); g. ghost shrimp (Neotrypaea californiensis); h. gaper clam(Tresus capax); i. tanaid (Leptochelia spp.)

Muddy Sand – Sand

a.

b.

c.

d.

e.

f.

g.

h. i.

a. pill bug (Gnorimosphaeroma oregonense); b. nereid worm (Nereis spp.); c. littleneck clam (Protothacastaminea); d. rockweed (Fucus distichus); e. bay mussel (Mytilus edulis); f. butter clam (Saxidomusgiganteus); g. gammarid amphipod (Eogammarus confervicolus); h. corophid amphipod (Corophium spp.)

Gravel – Gravel Cobble

a.

b.

c.

d.

e.

f.

g.

h.


Structure: a scaled perspective

Structure is often the fundamental elementof habitat. The observed complexity ofstructure is dependent upon the scale atwhich an environment is scrutinized. Atfirst glance (a), tidal flats appear generallyvoid of structure relative to nearby marshesand ee lg ra s s meadows . Upon c lose rexamination (b), the structure of the uppersed iment hor i zon i s apparent , wi thdifferent strata sustaining a myriad oforganisms, many of which are importantfood items for both fish and wildlife. At agreater distance (c), it is readily apparentthat the tidal flats are part of a greatercomplex of habitat types, which interact toaddress the many habitat requirements offish and wildlife. In examining structure,the investigator must be aware of thedifferent scales of structure that occur, andhow structure at many scales contributesto the biological productivity of shorelineenvironments.

a

b

c


water column, and is therefore easily retrievedand consumed by deposit and filter feeders.Within high energy environments, coarsesediments (e.g. coarse sand, gravels, andcobbles) dominate the tidal f lat surface.Detritus is often not readily available at thesurface. It may be found within the intersticesof coarse sediments where these localized lowenergy environments allow detritus to settle.This detritus is available to deposit feedersthat can burrow within these substrates.Spec i a l i z ed phy s i c a l and behav ioura ladaptations allow specific organisms to accessdetritus within specific substrates. As a result,the type of organism that may be found on at ida l f l a t i s o f t en dependent upon theavailability of detritus as food.

Detritus feeders, and the organisms that feedupon them, constantly modify the tidal flatenvironment. Conspicuous signs of animalactivity include tracks, holes, depressions andmounds (Figure 2.3). The fecal pellets of tidalflat inhabitants are deposited on the surface,forming a flocculent layer that is both foodand living space for others. The activity oforganisms increases the structural complexityof sediments. This change in complexity oftena l t e r s the su i t ab i l i t y o f sub s t r a t e s f o rparticular organisms. It may increase ordecrease the number of species or number ofindividuals that may inhabit substrates.Organisms, through modification of thestructural complexity of substrates, are oftenstrong determinants of the assemblage oforganisms that may inhabit a tidal flat.

2.3 Eelgrass Meadows

Eelgrass grows in firm mud to sand substrateswithin low energy environments at depthsbetween +1.8 m and -6.6 m chart datum(Figure 2 .4 ) . It o ccu r s w i th in wa t e r scharacterized by salinities of 10 to 30 gramsof salt per liter of water (10 to 30 parts perthousand). The upper limit of intertidaldistribution is attributable to desiccation. Thelower limit of distribution is determined bya number of contributing factors including

substrate type, energy regime, and l ightintensity.

Eelgrass meadows (Figure 2.5) s tabi l izesediments and provide refuge and food for avast array of organisms. In summer months,the blades of eelgrass are colonized by largenumbers of diatoms, small single celled algaethat form a fuzzy brown film. Detritus anduna s soc i a t ed bac t e r i a soon becomeincorporated in this f i lm. This diatom-detritus-bacteria film, together with decayingeelgrass leaves, is an important food sourcefor many protozoans, microscopic worms, andsmall crustaceans that are, in turn, food forother organi sms . Ee lgra s s prov ides thestructure upon which the film is established.

Figure 2.3 Tracks, holes, depressions andmounds created by tidal flat inhabitants.

Figure 2.4 Eelgrass growing within firm sandsubstrates.


Juvenile chum salmon (Oncorhynchus keta) areespecially dependent on eelgrass. Eelgrasssustains two key functions of productivejuvenile salmon habitat: refuge and food. Thestems and blades of eelgrass provide excellentcover. Eelgrass meadows sustain many smallsediment-dwelling invertebrates at densitiesfar greater than that of adjacent unvegetatedflats. Harpacticoid copepods are one of themore common of these invertebrates. Thesesmall crustaceans are the most important preyitem of juvenile chum salmon during theirresidency within estuaries.

The high numbers of harpacticoid copepodsfound within eelgrass meadows are a functionof the structural complexity of the eelgrassstem-root-rhizome-sediment zone (Figure2.6). This zone extends from immediatelyabove the surface of the sediments to anapproximate depth of 10 cm. The complex oftwisted roots, rhizomes and shoots providesrefugia for copepods from currents; many ofthe small crustaceans would otherwise becarried off as drift. This complex also capturesand retains detritus, a key food item forcopepods.

The localized concentration of copepodsprovides juvenile chum salmon with a readilyexploitable food source within a system thatalso provides these fish with ideal refuge frompredators. The structure provided by eelgrass

systems sustains important rearing functionsfor juvenile chum salmon.

The dominant herbivores in eelgrass systemsare waterfowl. Black brants (Branta bernicla),Canada geese (Branta canadensis), Americanwigeons (Anas americana), scoters (Melanittaspp.) and canvasbacks (Aythya valisineria) feedon the blades of eelgrass. While staging duringmigra t ion , l a rge f locks can consume asubstantial volume of eelgrass. Localizedforaging can cause considerable thinning ofeelgrass, in some instances sufficient to creatediscernable open water patches within ameadow. The creation of patches increases thestructural complexity of the meadow. Not onlydo patches differ structurally from adjacentstands of eelgrass, edges created along theinterface of patches and eelgrass s tandsintroduce an additional structural element tothe meadow.

Edges prov ide funct ions for spec ie scharacteristic of the interfacing elements ofopen water and eelgrass stands. Some of thesespec ie s may be spec ia l i s t s o f edgeenvironments. For example, species may useopen water for feeding forays, readily retreatinginto the eelgrass for refuge when threatenedby predators.

Numerous species of fish also use eelgrassmeadows for spawning. The use of eelgrass for

Figure 2.6 High numbers of harpacticoidcopepods occur within the stem-root-rhizome-sediment zone of eelgrass.

Figure 2.5 Eelgrass meadows of Boundary Bay,Fraser River estuary.


spawning can be especially pronounced. Pacificherring (Clupea harengus pallasi) use the bladesof eelgrass as a spawning medium. Suspendedwithin the water column, the blades are readilyaccessible to females. A single female herringmay deposit from 9000 to 38000 adhesive eggsdirectly onto the blades (Figure 2.7). Eelgrasscan carry more than 500 eggs per linear 25 mmof blade. The value of eelgrass as a spawningmedium is attr ibutable to the structureprovided by the blades.

2.4 Tidal Marshes

Tidal marshes vary in plant species compositionand diversity throughout estuaries. Variationcan be rather dramatic within larger estuaries.For example, the tidal marshes of the FraserRiver estuary may be categorized as eitherlower or upper estuary marshes according tothe composition and diversity of plant species.The geographical boundary between these twomarsh categories appears to be related to theupstream limit of the salt wedge within thees tuary. Lower e s tuary marshes occurdownstream of this location while upperestuary marshes occur upstream of thislocation. The salt wedge is a primary structuralelement that appears to determine speciescomposition and dominance within estuarinemarshes.

2.4.1 Lower Estuary Marshes

Marshes of the lower estuary are characterizedby distinctive vegetation zones that occur alonga vert ical gradient. Substrate e levat ionsdetermine the extent and duration of tidalinundation and, in turn, the species that inhabitthese zones . A s ing le spec ie s typ ica l lydominates each of these elevational zones.

Salt, brackish and fresh tidal marshes occurwithin the lower estuary (Figure 2.8). Each typeis defined by the prevailing salinity regime andcharacterized by a distinct assemblage ofdominant plant species.

The southern margin of the delta front of theFraser River estuary is characterized by high

salinities within both interstitial soil andambient waters. Salt marsh is the dominantmarsh type and is characterized by species thatcan tolerate high salinities. Such species includesaltgrass (Dist ichl i s spicata) , pickleweed(Salicornia virginica) and arrowgrass (Triglochinmaritimum). Dune barley (Elymus mollis)occurs within the higher elevations of saltmarshes where well draining sands and gravelsprevail.

Brackish marsh is the dominant marsh typewithin the downstream-most reaches of themain distributary channels of the estuary.Intermediate salinities occur within bothinterstitial soil and ambient waters of brackishmarshes. Characteristic species of brackishmarshes inc lude Lyngby’s s edge (Carexlyngbyei), Baltic rush (Juncus balticus), tuftedhairgrass (Deschampsia cespitosa), Americanthreesquare (Scirpus americanus), softstembulrush (Scirpus validus), hardstem bulrush(Scirpus acutus), and, despite its name, saltmarsh bulrush (Scirpus maritimus).

Fre sh marshes a re loca ted wi th in thedistributary and main channels of the FraserRiver several kilometres upstream of the deltafront where tidal influence is still pronounced.Characteristic species of the fresh marsh typeinc lude creeping spike rush (Eleochar i spalustris), softstem bulrush, hardstem bulrush,Lyngby’s sedge, broadleaved cattail (Typhalatifolia) and a variety of grasses, including reed

Figure 2.7 Eelgrass is a common spawning me-dium for herring.


Figure 2.8 Typical species composition and zonation of tidal marshes within the lower estuary of the FraserRiver.

spike rush

Lyngby’s sedge

broadleaved cattailreed canary grass

Baltic rushsoftstem bulrush

American threesquare

Lyngby’s sedge

dune barley

saltgrass

pickleweedarrowgrass

Fresh Marsh

Brackish Marsh

Salt Marsh


canary grass (Phalari s arundinacea ) andmannagrass (Glyceria spp.).

The plants that dominate salt marshes do sobecause they are able to cope with thephysiological stresses imposed by high salinitiesand extended periods of tidal inundation. It isthe tolerance of, and not the preference forthese environmental conditions that allowsthese plants to dominate the assemblage.

Interstitial soil and ambient water salinitiesdecrease with increasing distance upstream ofthe delta front. The decreasing role of salinityas an environmental s t ress removes thecompetitive advantage of those species tolerantof h igh sa l in i t i e s . With in brack i shenvironments, salt marsh dominants arereplaced by other species tolerant of lowsalinities. Due to their tolerance of lowsalinities, brackish marsh species are conferreda competitive advantage over many fresh marshspecies.

The transition from brackish to fresh waterenvironments is also accompanied by a changein the assemblage of dominant species .Tolerance of low salinities is no longer acompet i t i ve advantage . The change indominant species, however, is not as drastic asthat which accompanies the transition fromsalt to brackish marsh. Some species, such asLyngby’s sedge, maintain dominance within aspecific zone. These species possess othercharacteristics, such as a greater tolerance fort ida l inundat ion , tha t confer them acompetitive advantage over other fresh marshspecies. Regardless of the assemblage ofdominant species, the distinct zonation ofdominants characteristic of salt and brackishtidal marshes is maintained within the freshtidal marshes of the lower estuary.

The habitat functions provided by tidalmarshes for fish and wildlife are dependentupon marsh type. For example, salt tidalmarshes possess poor vertical structure; theplants are short in habit. For many smallperching birds, these marshes are inadequatefor nesting and refuge. In contrast, brackishand f re sh t ida l marshes a re o f ten used

extensively for nesting and refuge. Broadleavedcattail, softstem bulrush and hardstem bulrushprovide good vertical structure for nesting andrefuge. Through its influence on the type oftidal marsh expressed, the prevailing salinityregime determines the habitat functionsprovided for fish and wildlife.

2.4.2 Upper Estuary Marshes

The upper estuary is characterized by periodsof tidal inundation that are shorter in durationthan those periods characteristic of the lowerestuary. The decreased duration of t idalinundation removes the competitive advantageof plant species that can tolerate extendedperiods of inundation. The decrease in tidalinundat ion impact s both the spec ie scomposition of marshes and the prevalence ofdistinct zones of dominant species along avertical gradient.

The remova l o f the s t r e s s o f ex tendedinundation allows a greater number of speciesto compete for space within the intertidalzone. As a result, many species that are alsocommon to non-tidal fresh wetlands areprevalent within the fresh tidal marshes of theupper estuary. Such species include woollybulrush (Scirpus cyperinus), beaked sedge(Carex rostrata), water sedge (C. aquatilis),shore sedge (C. lenticularis), reed canary grassand bluejoint reed grass (Calamagro s t i scanadensis). Fresh marshes of the upper estuaryare characterized by a relatively high diversityof species. Distinctive zones of dominantspecies organized along a vertical gradient arerarely encountered. Other environmentalfactors, such as grade, soil type and saturation,often have a greater influence on speciescompos i t ion and dominance than t ida linundation.

2.5 Riparian Woodlands

Riparian woodlands occur within, and inproximity to, shoreline environments. Speciescomposition and dominance is related to theinfluence of both tidal and riverine water levelregimes. Three riparian woodland types may


be identified within estuaries, namely tidalswamp, floodplain woodland and high waterwoodland.

2.5.1 Tidal Swamp

Tidal swamps occur within the highestelevations of the intertidal zone, where tidalinundation is of limited duration and occurs,at most, during every other high tide event.The plant assemblage is dominated by shrubssuch as willow (Salix spp.) (Figure 2.9), redosier dogwood (Cornus stolonifera), ninebark(Physocarpus capitatus ) , black twinberry(Lonicera involucrata), cascara (Rhamnuspurshiana) and hardhack (Spiraea douglasii).Trees, such as red alder (Alnus rubra) andblack cottonwood (Populus t r i chocarpa )inhabit the highest elevations of tidal swamps.Where there are breaks in the cover of theshrubs, marsh species often dominate. Thestructure provided by the marsh-woodlandcomplex affords nesting opportunities forsmall passerines and waterfowl.

2.5.2 Floodplain Woodland

Floodplain woodlands lie above the normalhigh tide elevation (Figure 2.10). They areflooded during freshet and extreme stormevents . Floodplain woodlands are often

characterized by a mix of deciduous andconiferous trees. Dominants of the speciesa s s emb lage inc lude red a lde r, b l a ckcottonwood and western redcedar (Thujaplicata). Shrub species that may occur alongthe perimeter or beneath the tree canopyinclude willows, Indian plum (Osmaroniace ra s i f o rmi s ) , r ed e lderberry (Sambucusra c emo sa ) , r ed o s i e r dogwood , b l a cktwinberry, snowberry (Symphoricarpos albus),ninebark, salmonberry (Rubus spectabilis) andthimbleberry (R. parviflorus).

Large trees within floodplains are often usedby a variety of bird species. Eagles and hawksoften nest within the crotch of primarybranches near the crown of large blackcottonwoods. Herons establish rookeriesthroughout large stands of trees (Figure 2.11).Western redcedars are often selected fornesting and roosting by large owls. Cavitynesters utilize black cottonwoods extensively(Figure 2.12).

2.5.3 High Water Woodland

High water riparian woodlands are defined bystands of shrubs and trees above the normalh igh wa t e r mark o f the sho re l ineenvironment. The assemblage of p lantsconsists of species from both floodplain and

Figure 2.9 Willow dominated tidal swamp,Bedford Channel, Fraser River.

Figure 2.10 Cottonwood dominated floodplainwoodland, tidal reach of Kanaka Creek.


Habitat partitioning:selective use of structure

Natural shoreline environments typically sustaindiverse assemblages of plants. The structuralelements of these assemblages are dependentupon the plant species that comprise eachassemblage. Partitioning of these elements bywildlife allows for the compatible use of shore-line habitats by several species. Such use is ex-emplified by three bird species that often nestalong shorelines. Yellow-headed blackbirds(Xanthocephalus xanthocephalus; above) prefer tonest amongst stems of softstem or hardstembulrush, or mixed stands of bulrush and broad-leaved cattail. Cattail stands are the preferrednesting sites of red-winged blackbird (Agelaiusphoeniceus; centre). Brewer's blackbirds (Euphaguscyanocephalus; below) may be found nestingwithin shrub swamps and riparian thickets.


Figure 2.12 A common flicker (Colaptes auratus)utilizing a cavity within a black cottonwood.

Figure 2.11 Heron rookeries often occur within floodplain woodlands.

upland plant communities. Typically, as thelandward distance from the highwater markincreases, the interaction between the watertable and plants decreases. As a result, atransition in the composition of species andthe habits expressed by individual plants alsooccurs with increasing distance from the highwater mark. The number of species and thenumber of habits expressed determines thes t ruc tu ra l complex i t y o f a wood l and .Generally, structural complexity increaseswith an increase in either the number ofspecies or the number of habits expressed.

Structural complexity is further enhanced at

the interface between riparian woodland types.The areas defining the interface, or ecotones,a r e t r ans i t iona l env i ronment s tha t a r eimportant determinants of the overall valueof riparian woodlands as fish and wildlifehabitat. An ecotone is often characterized bya mingling of plant species common to eachwoodland type, as well as other species thatmay be specific products of the ecotone itself.Ecotones usually sustain a greater number ofplant species than the interfacing woodlandtypes. The diversity of fish and wildlife speciessustained by riparian woodlands is in largepa r t dependent upon the s t ruc tu ra lcomplexity of ecotones.

17

3Legislation and the Project

Review Process

3.1 Introduction

The majority of prospective shoreline construction andmaintenance projects will require approvals from regulatoryagencies. Federal and provincial agencies, regional districts, andlocal governments often have jurisdiction over components ofproposed shoreline works and, depending on the location andnature of the works, may require a formal application forapproval of the works.

This chapter is designed to assist proponents in navigating theproject review process by identifying the main agencies involvedin the process and discussing their respective mandates. It is aguide and, accordingly, should not be considered a stand-alonereference regarding the regulatory obligations of a project. Theregulatory bodies identified can be contacted by proponents foradditional advice and guidance.

The primary focus of the chapter is on Fisheries and OceansCanada as this federal agency has been empowered with thestrongest mandate to conserve natural resources within shorelineenvironments.

3.2 Fisheries and Oceans Canada and theFisheries Act

The Federal Constitution Act (1982) delegates authority for allfisheries in Canada to the federal government. The federalgovernment’s responsibilities for fisheries are set out in theFederal Fisheries Act, which provides for the management ofthe fisheries resource and the protection of fish and fish habitats.The Act is administered by Fisheries and Oceans Canada (DFO).Key to the project review process for shoreline developmentsare the habitat protection provisions of the Act, which are


administered by the Fish Habitat ManagementProgram (www.dfo-mpo.gc.ca/habitat/).

The Fisheries Act defines ‘fish’ to include:

“fish, shellfish, crustaceans, marine ani-mals”, and, “the eggs, sperm, spawn,larvae, spat and juvenile stages of fish,shellfish, crustaceans and marine ani-mals.”

Fish habitats are defined in the Act as:

“spawning grounds and nursery, rearing,food supply and migration areas onwhich fish depend directly or indirectlyin order to carry out their life proc-esses.”

Policy level clarification of these definitions isfound in the Habita t Conservat ion andProtection Guidelines (1998), which state that:

“Fish habitat therefore refers to: fresh-water, estuarine and marine environ-ments that directly or indirectly sup-port fish stocks or fish populations thatsustain, or have the potential to sustain,subsistence, commercial or recreationalfishing activities.”

Negative impacts on fish and fish habitatassociated with shoreline projects and relatedac t iv i t i e s a re prevented through theadministration and enforcement of the habitatprotection provisions of the Fisheries Act.Section 35 of the Act is a key provision in thisregard. Subsection 35(1) prohibits the harmfulalteration, disruption or destruction of fishhabitat. Subsection 35(2) provides the Ministerwith the power to author ize terms andconditions that would al low projects toproceed in compliance with the Act. Otherhabitat protection provisions of the FisheriesAct include Sections 20, 21, 22, 26, 27, 28,30, 34, and 37.

3.2.1 National Habitat Policy

The Policy for the Management of Fish Habitat(1986, the Habitat Policy) provides directionfor interpreting the broad powers mandatedby the habitat provisions of the Fisheries Act.The primary objective of the Habitat Policy isto:

“increase the natural productive capac-ity of habitats for the nation’s fisheriesresources, to benefit present and futuregenerations of Canadians.”

Productive capacity is defined as:

“the maximum natural capability ofhabitats to produce healthy fish, safefor human consumption, or to supportaquatic organisms upon which fishfeed.”

Progress toward this objective of a ‘net gain’in productive capacity of fish habitat is pursuedthrough the following policy goals of:

• conservat ion of the product ivecapacity of fish habitat;

• restoration of damaged fish habitat;and,

• development of fish habitat.

3.2.1.1 Fish Habitat Conservation Goal

The conservation of the current productivecapacity of fish habitat is the most importantcriterion used by DFO when assessing theacceptability of proposed works. Specifically,the goal of conservation, defined in the HabitatPolicy, is to:

“maintain the current productive capac-ity of fish habitats supporting Canada’sfisheries resources, such that fish suit-able for human consumption may beproduced.”

When there is a risk of potential damage tohabitat, DFO strives to prevent losses of fishhabitat.

Chapter 3 - Legislation and the Project Review Process Page 19

3.2.1.2 ‘No Net Loss’ Guiding Principle

The guiding principle of the conservation goalof the Habitat Policy is to achieve “no net lossof the productive capacity of habitats”. Inaccordance with this principle, DFO strives tobalance unavoidable habitat losses with habitatreplacement on a project-by-project basis.

To ensure ‘no net loss’, DFO will determine ifthe proposed works will cause the harmfulalteration, disruption or destruction (HADD)of fish habitat, defined as:

“any change in fish habitat that causesa reduction in the productive capacityof the habitat due to a reduction in itsability to support one or more lifeprocesses (e.g. reproduction, feeding,rearing and migration) of fish.”

In cases where the productive capacity of fishhabitat i s high, DFO wil l typical ly notauthorize a HADD. In those instances wherethe productive capacity of fish habitat is nothigh, an authorization of a HADD may beconsidered by DFO. An authorization may begranted contingent upon the implementationof various measures, including those used torestore or develop fish habitat so that ‘no netloss’ is achieved.

The application of the ‘no net loss’ guidingprinciple in the project review process isoutlined by the Habitat Conservation andProtection Guidelines (1998).

3.2.2 Project Review Process

Upon submiss ion of an appl icat ion forapprova l of shore l ine works , DFO wi l lundertake a detailed examination of thepotential impacts of the proposed works onfish and f i sh habitat . The proponent i sresponsible for providing all appropriate plans,specifications, studies and other informationrequired to allow an assessment of the potentialimpact of proposed works. Agency personnelwill assess the information provided by theproponent and, as required, visit the site and/or request additional studies to be completed

by the proponent. The proponent may berequired to:

• conduct baseline environmentalstudies to adequately describe thefish habitat potentially impacted byproposed works;

• develop a habitat mitigation and/orcompensation plan to offset impactsto f i sh hab i ta t , inc lud ing amonitoring program to confirmfulfillment of the plan’s objectives;

• assume the costs of implementingthe hab i ta t mi t iga t ion and/orcompensa t ion p lan and themonitoring program; implementcorrective measures, as required, toachieve compliance with the habitatmitigation and/or compensationplan;

• participate as required in publicinformation meetings; and,

• ensure that any agreement withDFO regard ing f i sh hab i ta tmitigation and/or compensationdoes not adverse ly af fect othernatural resources.

In determining the severity of potentialimpacts on fish and fish habitat, the factorsconsidered include:

• the potential for the project to affectfish, fish habitat and/or a particularfishery, as well as the nature of theeffect (e.g. physical disturbance,temperature change, flow alteration,release of nutrients or contaminants,reduct ion in dissolved oxygen,obstruction of fish migration);

• the presence or abundance of a fishspecies which is actively harvested orhas the potential to be harvested ina subsistence, commercial and/orrecreational fishery;

• whether the spec ie s a t r i sk i scons idered threa tened orendangered;

• the relative productive capacity ofthe habitat and/or degree to whichit supports an important life cycle


process (e.g. spawning, rearing,nursery, overwintering, food supply,migration);

• the availability and anticipated/proven effectiveness of mitigationand/or compensation measures;

• the relative proportion of availablehabitat which is af fected, bothregionally and locally; and,

• the habitat’s resilience to damageand the amount of time it wouldneed to recover to full productivity.

Following its examination of the proposedworks and the re su l t s o f any publ i cconsultation, DFO will assess whether theproject is likely to result in a net loss ofhabitat. If a loss is likely, DFO will thenevaluate the feasibility of proposed impactmitigation and compensation measures.

Depending on the outcome of its assessment,DFO may take one of the following actions:

• al low the project to proceed asproposed;

• a l low the project to proceed,but with additional mitigative/compensative measures followingspecific authorization from DFO; or,

• disallow the project in cases where thepotential loss to fish, fish habitatand/or a fishery is judged to beunacceptable.

3.2.3 Habitat Classification and Levelsof Protection

A key element of the project review process isthe classification of habitats in terms of thedegree to which they contribute to fisheriesproduction. This is to ensure that the level ofprotection, assessed in terms of the ‘no net loss’guiding principle, is appropriate for the habitatunder consideration. The Habitat Conservationand Protection Guidelines (1998) provides asimplified, three-tier classification approachfor defining appropriate levels of protection.

Critical habitats “require a high level ofprotection because of their importance in

sus ta in ing subs i s t ence , commerc ia l o rrecreational fisheries, their rareness, their highproductive capacity, the sensitivity of certainlife stages of the fish they support, etc.”Harmful alteration, disruption or destructionof critical habitat is typically not authorized.

Important habitats require a moderate levelof protection and “may include, for example,areas utilized by fish for feeding, growth andmigration, which, while important to the fishstock, are not considered critical. Areas in thiscategory usually contain a relatively largeamount of similar habitat that is readilyavailable to the stock. Habitat that has beendisrupted by past human activity may also fallinto this category.” Development that resultsin the harmful alteration or destruction ofimportant habitats usual ly can proceed,provided that appropriate mitigation andcompensation measures are in place.

Marginal habitats require a minimum levelof protect ion because they “have a lowproductive capacity and, according to availables tudie s , cont r ibute marg ina l ly to f i shproduction, but do have a reasonable potentialfor enhancement or restoration.” Developmentthat results in the harmful alteration ordestruction of marginal habitats can proceed,provided that appropriate mitigation andcompensation measures are in place.

Management options for project proposalsimpacting critical, important and marginalhabitats, in order of preference, consist of:

• project relocation;• project redesign;• mitigation of impacts; and,• compensation for impacts.

Compensation is the least preferred option andis only accepted when a HADD is authorizedby DFO.


3.2.3.1 Fraser River Estuary Shoreline HabitatClassification System

A regionally specific habitat classificationsystem is in effect for the entire Fraser Riverestuary shoreline. This colour-code basedsystem, developed under the auspices of theFraser River Estuary Management Program,classifies the overall habitat value of the estuaryshoreline and specifies requirements for futurehuman use and development. In highlyproduct ive ( i . e . c r i t i ca l ) hab i ta t a rea s ,development is not permitted unless theproponent can show that no alteration to ora l ienat ion of the habitat wi l l occur. Inmoderately productive (i.e. important) habitatareas, development is permitted subject tosatisfactory mitigation and/or compensationactions. In habitat areas of low productivity(i.e. marginal), development is permittedsubject to environmentally sound design andtiming restrictions.

Habitat areas of high, moderate and lowproductivity are colour coded red, yellow andgreen, respectively, on habitat classificationmaps . Fur ther de ta i l r egard ing th i sc l a s s i f i ca t ion sy s tem, and how i t i sincorpora ted wi th in the coord inatedenvironmental review process for the FraserRiver e s tuar y, may be obta ined f romwww.bieapfremp.org.

3.2.3.2 Courtenay River Estuary ShorelineHabitat Classification System

The Courtenay River Estuary ManagementPlan borrowed the concept of colour-codedshorelines for its own classification system.The habitat and development classificationsystem utilized for the Courtenay River estuarynot only employs a three tiered colour-codebased system, it also divides the shoreline intothree distinct habitat zones; each zone isafforded its own colour code. The CourtenayRiver estuary classification system is presentedin Figure 3.1. The Plan and classificationsystem are described at www-heb.pac.dfo-mpo.gc.ca/english/cremp/.

3.2.4 Mitigation and Compensation

Projects often require mitigation and/orcompensation to maintain the productivecapacity of fish habitat. Not all impactsassociated with projects, however, can beadequately mitigated or compensated for. Insome instances, the impacts are of such a natureand magnitude that significant losses to theproduct ive capac i ty o f f i sh habi ta t a reinevitable. Such losses are not authorized byDFO.

A detailed inventory of fish habitat in andabout the proposed location of works istypically required as a component of theapplication for works submitted to DFO. Thisinventory allows DFO to properly evaluateimpacts on the productive capacity of fishhabitat. The validity of proposed mitigationand compensation measures is evaluated withregard to their ability to achieve DFO’s ‘nonet loss’ guiding principle. The inventorydocuments significant biophysical elements ofthe location of proposed works, including, butnot limited to, topography and bathymetry,substrates, drainage patterns and features, andthe species assemblage and areal cover of plantcommunities.

3.2.4.1 Mitigation

Mitigation is defined as those features of theplanning, design, construction and operationof works that minimize or avoid adverseimpacts on the productive capacity of fishhabitat.

The greatest opportunity to mitigate impactsto fish habitat is during the conceptual designphase o f a pro jec t . The loca t ion andconfiguration of proposed works can often bemanipulated to avoid productive fish habitat.

Const ruct ion windows for shore l inedevelopment are used as an effective mitigationtool. The construction windows allow in-waterworks at times when fish are not present and/or s ens i t i ve l i f e h i s tory s t ages a re notoccurring. Examples of sensitive life historystages include downstream migration of


juveni le f i sh , upst ream adul t spawningmigrations, spawning, egg incubation or fryemergence. As the timing of these events variesaccording to location as well as climaticconditions, local DFO personnel should beconsulted regarding construction scheduling.

3.2.4.2 Compensation

Compensation is defined as the modificationor c rea t ion o f f i sh hab i ta t to o f f s e t

unmitigable impacts associated with proposedworks so as to maintain the overall productivecapacity of fish habitat.

DFO has developed a hierarchy of preferencesfor compensa t ion opt ions . In order o fpreference, the options are:

• creation of similar habitat at or nearthe development site and within thesame ecological unit (onsite);

Figure 3.1 Habitat and development shoreline classification system for the Courtenay River estuary.


• increasing the productive capacity ofex i s t ing habi tat a t or near thedevelopment site and within thesame ecological unit (onsite);

• creation of s imilar habitat in ad i f f e rent eco log ica l un i t tha tsupports the same stock or species(offsite);

• increasing the productive capacity ofa dif ferent ecological unit thatsupports the same stock or species(offsite); and,

• increasing the productive capacity ofexis t ing habitat for a di f ferentspecies of fish either on or off site.

In deve loping compensat ion s t ra teg ies ,proponents are obliged to follow the hierarchyof preferences. If a strategy embraces a lesspre fe rab le opt ion, the proponent mustadequately demonstrate, utilizing technical and/or financial criteria, why more preferableoptions are not feasible.

To determine the extent of compensationrequi red wi th in e s tuar ine and mar ineenvironments, DFO personnel often define thequantity of new habitat to be created to offsetunmitigable losses of habitat. The quantity ofnew habitat to be created is dependent upon:

• the productive capacity of impactedand created habitats;

• the interim loss of productivityassociated with created habitatsachieving full productivity; and,

• the risk of failure associated with theproposed compensation habitat.

3.2.4.3 Habitat Compensation Authorization

When DFO makes a decision to authorize aHADD of fish habitat, a legal Authorizationpursuant to Subsection 35(2) of the FisheriesAct is issued.

The Authorization includes a description ofthe works to be undertaken, specifies theperiod during which the compensation worksare to be completed, and summarizes themonitoring program required. The objective

of the monitoring program is to assess theefficacy of constructed habitats in achievingcompensation habitat design objectives.

3.3 Other Authorities and Actsof Legislation

This section presents agency mandates andlegislation, in addition to that of DFO andthe Fisheries Act , frequently encounteredduring the project review process for worksproposed within shoreline environments.

3.3.1 Federal Agencies

3.3.1.1 Canadian Environmental AssessmentAgency

The Federa l Canadian Envi ronmenta lAssessment Act (CEAA) was established in 1994to ensure that environmental effects of federalprojects are carefully considered, to promotesustainable development, and to ensure publicparticipation in the environmental assessmentprocess. The CEAA process may be triggeredunder Section 5 of the Act if a federal authority:

• proposes a project;• grants money to a project;• grants an interest in land to a

project; and/or• exerc i s e s a r egu la tory duty in

relation to a project.

For example, the CEAA process is triggered ifDFO authorizes a HADD. The CEAA processincludes an environmental assessment, whichmay range from a screening document forroutine proposals to a comprehensive studyand panel review for large-scale projects withsignificant environmental impacts. For mostprojects, the CEAA process is administered bythe regulatory agency that exerc i ses i t slegislative authority in relation to the project.The regulatory agency administering processis responsible for the decision as to whether ornot the project proceeds. The proponent istypica l ly responsible for address ing theinformation needs of the CEAA regulatoryagency.


The CEAA process was harmonized with theProvincia l Environmental As se s sment Actproject review process through the “1997Canada-British Columbia Agreement forEnvironmental Assessment Cooperation”. Theagreement was applied to projects subject toenvironmental legislation of both governments.The agreement expired in 2002. The FederalAn Act to Amend the Canadian EnvironmentalAssessment Act is currently being reviewed bythe federal government. The EnvironmentalAssessment Act has recently been amended bythe provincial government. As a result, thefederal and provincial governments haveproposed to amend and extend the 1997agreement on an interim basis until a new longterm agreement can be negotiated based on thenew legislation of both governments. Updatesand further information on harmonization offederal and provincial environmental reviewprocesses may be obtained from www.ceaa-acee.gc.ca.

3.3.1.2 Canadian Coast Guard, Fisheries andOceans Canada

The Canadian Coast Guard administers theFedera l Navigable Water s Protec t ion Act(NWPA). Section 5 of the Act regulates anyactivity that could impact navigable waters.Navigable waters include:

• “any body of water capable, in itsnatural state, of being navigated byfloating vessels of any descriptionfor the purpose of transportation,recreation or commerce”;

• “a canal and any other body of watercreated or altered for public use”;and

• “any waterway where the publicr ight o f nav iga t ion ex i s t s bydedicat ion of the waterway forpublic purposes, or by the publichav ing acqui red the r ight tonavigate through long use”.

Approval for any project within navigablewaters must be obtained from the NavigableWaters Protection Division of the CanadianCoast Guard (www.pacific.ccg-gcc.gc.ca/nwp/).

Sections of the NWPA are included on the LawList of the Federal Canadian EnvironmentalAssessment Act and, with their application to aproject, may trigger a CEAA environmentalassessment.

3.3.1.3 Port Authorities

Ports and harbours are a common feature ofcoastal British Columbia; many of thesefacilities are managed by Port Authorities. PortAuthorit ies are governed by the FederalCanada Marine Act, which replaced the FederalCanada Por t Corpora t ion Ac t , HarbourCommissions Act and Public Ports and HarbourFacilities Act. Part 1 of the Act provides forthe e s tab l i shment o f 18 Canada Por tAuthorit ies including: Fraser River PortAuthority; Nanaimo Port Authority; NorthFraser Port Authority; Port Alberni PortAuthority; Prince Rupert Port Authority; and,Vancouver Port Authority. These Authoritieshave broad powers of administration over landand water in their jurisdictions, includingmanagement of federal real property, issuanceof leases and licences, land use planning andestablishment of bylaws. Part 2 of the Act alsoprovides for the establishment of public portauthorities for those ports and harbours notdes ignated as Canada Por t Author i t ie s .Proposed works in port jurisdictions are notto compromise the integrity and efficiency ofthe port or harbour system and the deploymentof resources. Approval must be obtained fromthe local authority prior to any works beingcarried out within the respective port.

Regulations made under the Federal CanadianEnvironmental Assessment Act stipulate howenvironmental assessments are to be conductedby Canada Port Authorities (www3.ec.gc.ca/EnviroRegs/). These regulations define theenvironmental assessment process to befollowed for specific types of projects. PortAuthorities conduct environmental assessmentsas part of the overal l administrat ion ofproposed land and water uses within theirjurisdictions.


3.3.1.4 Environment Canada

The estuaries of coastal British Columbiaprovide critical staging and breeding habitatfor migratory shorebirds and waterfowl. TheCanadian Wi ld l i f e Serv ice (CWS) o fEnvironment Canada manages migratory birdhabitat through authority provided by theFedera l Migrator y Bird s Convent ion Act(www.pyr.ec.gc.ca).

The Migratory Birds Regulations and theMigratory Bird Sanctuary Regulations areenabled by the Migratory Birds Convention Act.These regulations, respectively, address theprotection of migratory birds and migratorybird sanctuaries. Sections of both regulationsare included in the Law List of the FederalCanadian Environmental Assessment Act and,accord ing ly, may t r igger a CEAAenvironmental assessment.

The Environmental Protection Branch ofEnvironment Canada i s responsible foradmini s te r ing the Federa l CanadianEnvironmental Protection Act , the FederalCanadian Environmental Assessment Act andSection 36 of the Federal Fisheries Act. Section36 prohibi t s the depos i t of de le ter ioussubstances in waters frequented by fish unlessauthorized by regulation under the FisheriesAct. Environment Canada’s responsibilities forSection 36 are derived from a Memorandumof Understanding with DFO. The Minister ofFisheries and Oceans Canada, however, remainsaccountable to Parliament for all componentsof the Fisheries Act.

3.3.2 Provincial Government Agencies

3.3.2.1 Ministry of Water, Land and AirProtection

The Environmental Stewardship Division ofthe Mini s t r y o f Water, Land and Ai rProtection (MWLAP) recommends standardsand best practices for works and relatedactivities within shoreline environments.These recommendations are considered as:terms and conditions provided by a HabitatOfficer pursuant to Sections 40 and 42 of Part

7 of the Provincial Water Act Regulation for aNotification pursuant to Section 44; and,advice for applications pursuant to Section 9of the Provincial Water Act. Application andreporting standards are provided by MWLAP.The information provided by applications andreports is util ized by the EnvironmentalStewardship Division to maintain and restorefish and wildlife species and their habitats.

The Inspector of Dikes Office, Public SafetySection, is responsible for administering theProvincial Dike Maintenance Act , whichprovides the legislative basis for the operationand maintenance of public dikes in BritishColumbia. The Inspector of Dikes Office isresponsible for the approval of all works in andabout dikes, joint inspections with localauthor i t i e s to moni tor and audi t d ikemanagement programs, and the issuance oforders to protect public safety.

The Environmental Protection Division ofMWLAP is responsible for administering theProvincial Waste Management Act , whichregulates the discharge of solid waste, effluentand emissions into the environment. Wastesmay only be discharged in accordance withpermits or approvals issued by MWLAP, aLiquid Waste Management P lan or theMunicipal Sewage Regulation of the Act. Part4 o f the Act , “Contaminated S i teRemedia t ion” , s e t s out ru le s fo r theidentif ication, remediation and l iabi l i tyassociated with contaminated sites. A numberof conditions can trigger the initial ‘site profile’requirements under this section, such assubdivision, rezoning, or development permitapplications for land that the applicant “knowsor reasonably should know is or was used forindustrial or commercial activity.”

Further information regarding the mandateand management activities of MWLAP maybe obtained at www.gov.bc.ca/wlap/.


3.3.2.2 Ministry of Sustainable ResourceManagement

Low lying coastal areas were the preferredloca t ions for s e t t l ements o f both Fi r s tNations peoples and early European settlers.Today, many of these areas sustain relics ofthese settlements that are of archaeologicala n d / o r h i s t o r i c a l s i g n i f i c a n c e . T h eArchaeology and Fores t s Branch of theM i n i s t r y o f S u s t a i n a b l e R e s o u r c eManagement (MSRM), under the legislativea u t h o r i t y o f t h e P r o v i n c i a l H e r i t a g eConservation Act, reviews applications forworks that may impact s ites that are ofarchaeological and/or historical significance.I n t h o s e i n s t a n c e s w h e r e p r o p o s e ddevelopment may damage archaeologicalsites protected under the Act, the Branch willadvise the applicant that an archaeologicalimpact assessment is required. A decision orr e c o m m e n d a t i o n r e g a r d i n g p r o p o s e ddevelopment is dependent upon the findingso f t h e i m p a c t a s s e s s m e n t . F u r t h e rinformation regarding the project reviewprocess as administered by the Archaeologyand Forests Branch may be obtained atwww.archaeology.gov.bc.ca.

The Ministry administrates the activities ofindependent government bodies that mayfacilitate and/or participate in the review and/or approval of proposed uses within shorelineenvironments. Three of the more relevant ofthese bodies include:

• Land and Water British ColumbiaInc.;

• Environmental Assessment Office;and,

• Land Reserve Commission.

Land and Water British Columbia Inc.

The Water Management Branch of Land andWater British Columbia Inc. is responsible forenforcing the provisions of the ProvincialWater Act (www.bc-land-assets.com/water/).Provisions within this piece of legislationpertain to any activities that could affect eitherthe volume of water flowing in a watercourse

(i.e. Section 8, “short term use of water”) orthe morphology o f the channe l o f thewatercourse (i.e. Section 9, “changes in andabout a stream”). An approval or license mustbe obtained from the Comptroller of WaterRights for works that may affect the flow ofwater and/or the physical environment of awatercourse.

Environmental Assessment Office

The Environmental Assessment Office (EAO)administers the Provincial EnvironmentalAssessment Act (www.eao.gov.bc.ca). The Actprovides a single review process to assess certainmajor projects and act iv i t ies in Bri t i shColumbia. The review takes into account abroad range of effects for al l reviewableprojects. Those effects assessed are categorizedas environmental, economic, social, health,cultural and heritage.

The Act addresses reviewable projects asdesignated by regulat ion, the ExecutiveDirector of the EAO, or the Minister ofSustainable Resource Management. Reviewableproject categories are industrial , energy,mining , water, was te , food proces s ing ,transportation and tourism. An environmentalassessment certificate is granted a reviewableproject upon acceptance of potential effectsidentified by the assessment and conditionsthereof, as required, that reduce the severityof such effects.

Constitutional responsibility for managementof the environment is shared between thefederal and provincial governments. As a result,pro jec t s sub jec t to the Prov inc ia lEnvironmental Assessment Act may be subjectto the Federa l Canadian EnvironmentalAssessment Act. Currently, a draft amendmentto the “1997 Canada-Bri t i sh ColumbiaAgreement for Environmental AssessmentCooperation”, as presented in Section 3.3.1.1,proposes that, for all reviewable projects,federal agencies will designate the process ofscreening or comprehensive study under federallegis lat ion to the provincial EAO. Eachgovernment retains autonomy over theirrespective decisions regarding approval of the


project; each government retains its decision-making role. The decisions are made on thebasis of shared information and are analyzedthrough a single process facilitated by the EAO.

Land Reserve Commission

Dikes are often constructed to prevent theflooding of agricultural lands. Many such dikesare constructed on lands within the provincialAgricultural Land Reserve (ALR). Proposedworks that could affect agricultural landswithin the ALR require approval from theLand Reserve Commission. In part, the LandReserve Commission governs uses and activitieson ALR lands. The Commission is granted itsauthority to govern such uses and activities bythe Provincial Land Reserve Commission Act,Agricultural Land Commission Act, and SoilConservation Act (apps.icompasscanada.com/lrc/).

3.3.3 Municipalities and RegionalDistricts

In urbanized areas, Municipalities and RegionalDistricts, as mandated under the ProvincialLocal Government Act, conduct project reviewsto assess compliance with municipal zoningbylaws. Proposals for the maintenance orrepair of existing facilities often fall under thejurisdiction of municipalities.

Munic ipa l i t i e s and Reg iona l Di s t r i c t sformulate Official Community Plans to set outland use zoning and other developmentrequirements. For shoreline developments,leave strips may be required, the width ofwhich are dependent on the environmentalsens i t iv i ty of the area . NeighbourhoodCommunity Plans further define land usezoning and other development requirementsfor specific areas within the municipality.

Many local governments have undertakenplanning exercises that define EnvironmentallySensitive Areas (ESA’s) or classify streams and/or shorelines according to fish and wildlifehabitat value. The ESA’s and classifications aretypically incorporated within the OfficialCommunity Plan.

The detailed review of development proposalsand re la ted act iv i t i e s (e .g . munic ipa linfrastructure improvements) often includes anassessment of environmental impacts. Adialogue with DFO, regarding issues pertainingto fish and fish habitat, is maintained throughan Environmenta l Rev iew Committeefacilitated by the Planning or EngineeringDepartments of the respective Municipality.Recommendations provided by DFO areincorporated within the response from theMunic ipa l i ty to the proponent ofdevelopment. Subsection 35(2) Authorizations,as required, are often included as a conditionof approval from the Municipality.

The Provincial Drainage, Ditch and Dike Actand Local Government Act provide localgovernments with the authority to undertakediking and drainage through local bylaws andImprovement Districts. Responsibility for theoperation and maintenance of dikes constructedby local diking authorities, diking districts andmunic ipa l i t i e s i s ve s ted wi th theseorganizations. However, supervision andapproval of all works associated with publicdikes is the responsibility of the provincialInspector of Dikes Office.

29

4Facilities and

Structures

4.1 Introduction

Structures and facilities such as bridges, wharves and marinas areprevalent within developed shoreline environments. In the past,these features were designed with little consideration of theirimpacts upon fish and wildlife habitats. The design process hasevolved to where environmental design criteria are now a primaryconsideration. This evolution has been facilitated by environmentalagencies through the various project review processes administeredwithin coastal British Columbia.

This chapter consolidates state-of-the-art environmental designcriteria that are frequently applied on a project-by-project basis.The feasibility of development proposals, in terms of fish andwildlife habitat conservation, is contingent upon the incorporationof such criteria within the overall project design. The chapterspecifically addresses design elements such as size, footprint,materials, location and surface texture, all of which can bemodified to reduce the impacts of structures and facilities onshoreline environments.

Although design issues pertaining to the mitigation of impactson the nearshore subtidal environment are addressed, the focusof the chapter is primarily on the foreshore environment.Furthermore, environmental design criteria for dikes are presentedin Chapter 6, as dikes possess some unique design issues that aremore appropriately considered in a separate context.

4.2 Description of Structures

4.2.1 Types of Structures

Foreshore structures may be grouped into one of two categories,those that are supported or anchored by piles, and those thatincorporate fills, revetments and slabs.


Pile supported and anchored structures include:

• bridges (Figure 4.1) and piers;• docks, floats (Figure 4.2) and buoys;• log booms (Figure 4.3); and• timber walkways.

Fill, revetment and slab structures include:

• bridge and pier abutments (Figure4.4) and footings;

• wharves (Figure 4.5) and otherbulkheads;

• access ramps and spillways;• dikes, training walls (Figure 4.6),

breakwaters and groynes; and• utilities such as pipelines and cables,

pump stations and floodboxes, andsewer outfalls.

The footprints associated with facilities andstructures within these two categories differsignificantly. The footprint is defined as thatarea of habitat that is either removed or coveredby the structure. The definition does notinclude that area that is shaded by the struc-ture. Typically, pile supported and anchoredstructures minimize the footprint on foreshoreand nearshore subtidal environments. Incontrast, fill, revetment and slab structures arecharacterized by relatively large footprints(Figures 4.7 and 4.8).

4.2.2 Conventional Material Types

Shoreline structures may be constructed ofwood, rip rap, concrete and/or steel.

4.2.2.1 Pile Supported and AnchoredStructures

The use of wood as a construction materialincludes the use of wood preservatives. Woodpreservatives significantly extend the life ofwood structures. Their effectiveness lies withtheir toxicity to organisms that would otherwisebore into and/or consume the wood, eventuallycompromising the integrity of the structure.

Historically, many pile-supported structureswere constructed almost entirely of wood. The

Figure 4.1 Arterial road bridge, Middle Armdistributary channel, Fraser River.

Figure 4.2 Marina floats, Deas Slough, Main Armdistributary channel, Fraser River.

Figure 4.3 Log booms at Timberland Basin,Annieville Channel, Fraser River.

Chapter 4 - Facilities and Structures Page 31

wood, both timbers and piles, was treated withcreosote. Although still required by someconstruction standards (e.g. 1988 Bridge Code(CAN/CSA S6-88)), recent use of creosotetreated timbers and piles has been primarilywithin high salinity brackish and salt waterenvironments, where it is the wood preservativethat is most effective in deterring marine boreractivity.

Chromated copper arsenate (CCA) treatedtimbers are often used for the decking andsuperstructures of piers, wharves and light dutystructures such as pedestrian boardwalks andviewing platforms. CCA treated piles may beused for light duty structures where the bearingload is small and only a shallow foundationdepth is required.

Douglas fir, which is structurally stronger thanhemlock and ponderosa pine, is the preferredspecies for construction of wood structures.Douglas fir, however, is not effectively treatedby CCA. Ammoniacal copper zinc arsenate(ACZA) is more effective than CCA in thetreatment of Douglas fir. New construction of

Figure 4.4 Pier abutment, Annieville Channel,Fraser River (inset: abutment during construction)

Figure 4.5 Wharves, Annieville Channel, FraserRiver.

Figure 4.6 Steveston Jetty, delta front at SturgeonBank, Fraser River.

Figure 4.7 Slab (access ramp) and pile supported(pier) structures, North Arm distributary channel,Fraser River.

The difference in the areal extent of the footprintsof a typical pile supported structure and a slabstructure is readily apparent. The pile-supportedstructure accommodates a highly productive inter-tidal fresh marsh. In contrast, the slab is marginalhabitat for fish and wildlife.


wood structures typically utilizes timbers andpiles treated with ACZA.

Concrete and steel are often used for heavy-duty structures. The use of steel for structuresis often preferred by design engineers andconstructors as it is amenable to modificationduring or after installation. For example, if apile is driven too deep, whereby the top of thepile is below design elevation, it is far easier tofix an extension to a steel pile (welded steel)than to a concrete pile (formed concrete withrebar connection).

4.2.2.2 Fill, Revetment and Slab Structures

Wood is the least utilized material type for fill,revetment and slab structures. Its use isprimari ly as a revetment for small-scalebulkheads and as the superstructure andfoundation for small floodboxes and pumpstations. Historically, creosote treated woodwas used extensively for such structures. Theuse of creosote treated wood, as for pilesupported and anchored structures, now occursprimarily within high salinity brackish and saltwater environments. For low salinity brackishand fresh water environments, the use of ACZAtreated wood is now the construction standard.

Rip rap is generally used for erosion protection,and is the primary material used for theconstruction of training walls, breakwaters,and groynes. As erosion protection, it is used

to armour the lower banks of dikes and naturalshore l ines , and the marg ins o f p ie rfoundations, bridge abutments, and otherconcrete works that may be exposed toexcessive fetch, wake and currents.

Steel sheet pile is used to retain structural fillsassociated with wharves and other bulkheads.It is often used within marina basins to stabilizebanks cut and exposed during dredging.

Concrete is the primary construction materialfor free standing and foundation structures.These include bridge abutments, columns andcolumn footings, foundations and casings forpipelines, cables and storm sewer outfalls, andthe lower superstructures and foundations ofpump stations and floodboxes. Prefabricatedconcrete structures, such as lock-blocks, areused to contain fill.

4.3 Environmental DesignParameters

There are several design elements that can bemodified to reduce the impact of structures.

These include:

• size and footprint;• materials;• location; and• roughness.

Figure 4.8 The use of piles (left) rather than fill (right) can significantly reduce the footprint of a structurewhile retaining the same usable area.


4.3.1 Pile Supported and AnchoredStructures

4.3.1.1 Size and Footprint

Size relates to the usable area of a structure.For pile supported and anchored structures, sizedetermines the area shaded by the structure.An increase in size decreases the intensity oflight and increases the area shaded (Figure 4.9).

Shading can have a significant impact on thevigour of intertidal marsh and nearshoresubtidal submergent plants such as eelgrass andkelp. The impact on plants can be eitherchronic or acute. Chronic impacts are thosethat do not eliminate plants entirely from theshaded area. Such impacts include reduced arealcover, vegetative production and/or seedproduction. Acute impacts are those thateliminate existing plants entirely, leavingaffected areas barren.

For both fixed and floating structures, theextent and intensity of shading may beminimized by incorporating perforations orlarge spaces within the decking (Figure 4.10).Light penetration may be achieved simplythrough incorporating larger spacings betweendeck planks, or utilizing an alternative decksurface, such as metal mesh. Such design consi-derations must, however, acknowledge thedesigned use for the deck area. The greatest

potential for user conflict is associated withstructures that are to be used extensively bypedestrians.

Fixed structures such as bridges, piers andwalkways should incorporate features thatincrease the diffusion of light upon underlyinghabitats. For all fixed structures, this can beachieved by increasing the height of thestructure above affected habitats (Figures 4.11and 4.12). For bridges, a further increase inthe diffusion of light to areas beneath thestructure can be achieved by splitting the deck(i.e. lanes) of the bridge.

For piers, diffusion may be increased byreducing the size of the structure withoutcompromising its designed use. For example,the conventional design for a pier incorporatesa deck with a long rectangular configuration,of constant width, that accommodates bothcargo handling and interim storage. In mostinstances, loading and unloading of cargo isrestricted to the most offshore portion of thepier; the nearshore portion of the pier isessentially a corridor utilized for the transportof cargo. As a resul t , the des ign widthrequirement for the nearshore portion of thepier deck is less than that for the most offshorepor t ion. According ly, the width of thenearshore portion may be reduced withoutcompromising the intended use of the pier(Figure 4.13).

Figure 4.9 The intensity of light is increased beneath a pile structure by incorporating several smaller decks inplace of one large deck to achieve design use objectives (adapted from Witherspoon & Rawlings 1994).


Floating docks are designed for installationwithin nearshore subtidal environments and aretypically less than 4 metres in width. Theimpact of floating docks on the submergentplant community is dependent on the depthof water beneath the structure. The shallowerthe water at low tide, the greater the potentialfor impact; accordingly, the width of the dockshould decrease with decreasing depth. In

general, the width of the dock should notexceed the depth of water. For example, at 3metres depth, the dock width should notexceed 3 metres.

4.3.1.2 Materials

New construction of wood structures withinshoreline environments utilizes timbers and

Figure 4.11 The intensity of light is increased and the area shaded is decreased by increasing the height of thepile structure (adapted from Witherspoon and Rawlings 1994).

Figure 4.10 Grating incorporated as part of the decking of structures can significantly decrease the extent ofshading (adapted from Witherspoon and Rawlings 1994).


Figure 4.12 Pile supported and anchored struc-ture, Chatham Reach, Pitt River.

Floating docks are linked to upland by a pedes-trian pier that spans approximately 125 linearmetres of intertidal fresh marsh and mudflat. Thefloating docks do not ground at low tide. The pieris high, narrow and is aligned in an east-westdirection. These design features minimize both theintensity and areal extent of shading of the marsh.

Figure 4.13 A reduction in the shoreward por-tion of a pier (top) increases the intensity of lightand reduces the area shaded; the intended use ofthe pier is easily maintained.

piles treated with preservatives. Although theyextend the life of structures, preservatives leachfrom treated wood, and as such, pose a threatto aquatic life residing in proximity to thewooden structure.

To mitigate impacts of treated wood uponaquatic life, projects must use wood productstreated to Best Management Practices (BMP)standards (Canadian Institute of Treated Woodand Western Wood Preservers Institute 1997).BMPs for the in-plant preservation of woodhave been recognized by Environment Canadaand Fisheries and Oceans Canada as a usefultool for agency staff, with the provisos thatthe BMPs must be updated as knowledgeimproves, and that even wood treated accordingto BMPs can have impacts on aquatic lifeunder certain conditions (Hutton and Samis2000). The BMP mark (Figure 4.14), a legaltrademark in the United States but withoutsuch status in Canada, is used in BritishColumbia by the Canadian Sof twoodInspection Agency to certify wood productstreated with preservatives according to BMPs.

In addi t ion to be ing t rea ted to BMPs

standards, creosote treated wood should beaged at least three months prior to in-waterinstallation. Aging allows some of the volatilecomponents to evaporate , cons iderab lyreducing the surface sheen often associated withcreosote treated wood installed within water.Effective evaporation is contingent upon thefree movement of air surrounding treatedtimbers and piles. Facilities storing treatedwood must have a contained drainage systemwhereby runoff from the surface of aging wooddoes not drain into a water body sustainingaquatic life.


Figure 4.14 BMP mark.

treated wood as a construction material withinshoreline environments, an integrated approachof material substitution and restricted use isrequired (Figure 4.15). Piles, bulkheads andbridges are ideal candidates for materialsubstitution. These structures can be feasiblyconstructed of either concrete or steel. Forexample, steel is quickly replacing treated woodas the material of choice for piles in manystructures. Recent decreases in the cost of steel,and the longer life of steel relative to treatedwood, provide an extremely cost effectivematerial alternative for many long tenuredstructures.

The decks of floating docks are typicallyconstructed of either CCA or ACZA treatedtimbers. Material alternatives are available;however, for small to medium scale projects,treated wood is currently the most practicalconstruction material. Concrete has been usedfor the decks of large docks; these are ratherelaborate structures that integrate the deck withconcrete floats.

Dock design should not use styrofoam blocksfor floatation. Styrofoam readily breaks apart;pieces may be ingested by animals, in particularbirds. High-density foam is an acceptableconstruction material for floats. It is bothenvironmentally benign and very cost effective.

A considerable volume of wood preservativeis delivered to shoreline environments bytreated-wood spl inters generated by therubbing of floating docks, booms and boatsagainst treated piles. Bumper timbers and pilesshould be protec ted wi th h igh-dens i typolyethylene wear strips.

4.3.1.3 Location

In all instances, structures should span theforeshore zone. The structure should notsignificantly modify the prevailing physicalprocesses where such modification wouldcompromise physical fish and wildlife habitatfeatures. For example, training walls and jettiesin estuaries must be assessed with regard totheir prospective impact on salinity andsedimentation regimes. In the past, such

The design of the wooden structure canincorporate features that minimize leaching ofcreosote from treated wood. Creosote ismobilized and leached from treated woodunder intense solar radiation. The design of thestructure must consider the extent of exposureof treated wood to direct sunlight; the mostsusceptible portions of a structure are those thatare infrequently or never submerged. Theleaching of creosote from emergent structurescan be minimized by incorporating designfeatures that enhance shading (e.g. overhangingdecks). Where adequate shading cannot beachieved, the design must pursue an alternativeconstruction material, such as ACZA treatedwood, concrete or steel.

Leachable toxins associated with CCA andACZA treated wood include copper, arsenate,zinc and chromate. Of these toxins, copperposes the greatest risk to aquatic life. When analternative to CCA-treated wood is notavailable for use, the wood must be treatedwith CCA-C. CCA-C is the most leachres i s tant of three formulat ions of CCAavailable for use.

Although CCA-C is the most leach resistantof the three formulations of CCA, woodtreated with this preservative should besubstituted with wood treated with ACZAwhen possible. ACZA is more leach resistantthan CCA-C.

In order to mitigate the impact of the use of


structures have caused changes in areal coverand plant species composition of foreshoremarshes, changes in areal cover of nearshoresubtidal eelgrass meadows, and changes in thesediment budget of foreshore and nearshoresubtidal mudflats.

The areal extent and intensity of shading onforeshore and nearshore subtidal environmentsmust be minimized by the design of thestructure, especially where the structure spansmarsh , ee lg ra s s meadows and beds o fmacroalgae. To adequately mitigate the impactof shading, the design must consider theorientation of the structure to the shorelinerelative to the position of the sun in the sky(Figure 4.16). For example, structures that havea southern aspect typically cause significantlyless shading of the foreshore and nearshoresubtidal environments than similar structuresthat have a northern aspect. Depending on theorientation of the shoreline to the position ofthe sun, structures may be aligned at an angleto the shoreline to minimize shading. Carefulanalysis of the prevailing light regime willdictate the appropriate alignment of thestructure.

4.3.1.4 Roughness

Roughness refers to the texture of the materialutilized for construction. In general, the greaterthe roughness, the greater the diversity ofmicrohabitats for aquatic organisms. Roughsurfaces trap organic material that in turn isboth habitat and food for a myriad of aquaticinvertebrates. Rough surfaces within salt waterenv i ronments a l so prov ide po int s o fattachment for encrusting organisms, such asmacroalgae, mussels and barnacles.

Concrete piles possess coarse surfaces that allowthe ready attachment of encrusting organismswithin high salinity brackish and salt waterenvironments. In contrast, steel piles possess asmooth surface that deters the establishmentof a vigorous encrusting community. Althoughtreated wood piles possess a rough surfacetexture that would normally permit theattachment of encrusting organisms, the

Figure 4.15 Viewing platform, Burnaby Fore-shore Park, North Arm distributary channel,Fraser River.

The platform design, through incorporation ofsteel and concrete as its primary constructionmaterials, mitigates the impact of material typeson the shoreline environment.

Figure 4.16 Relationship between shading andaspect of structures.

Northern Aspect Southern Aspect


preservatives, especially with new piles, detercolonization of the pile surface.

Concrete floats, in contrast to concrete piles,typically have a finished surface that is smooth.Steel drum floats have a surface texture that issimilar to that of steel piles. In high salinitybrack i sh and sa l t wate r env i ronments ,increasing the surface roughness of floats is nota pract ica l considerat ion, as encrust ingcommunities can substantially increase theweight of docks, thereby compromising thebuoyancy of the entire dock structure.

Increasing the surface roughness of piles forthe purpose of increasing local productivity isbest achieved within high salinity brackish andsalt water environments. Furthermore, thepotent ia l for enhancing the encrus t ingcommunity at a particular location is greatestfor support piles. Anchor piles, which tetherdocks and other floating structures that moveup and down with fluctuating water levels,require a relatively clean surface to ensure theunhindered movement of structures.

4.3.2 Fill, Revetment and SlabStructures

4.3.2.1 Size and Footprint

The footprint of fill, revetment and slabstructures can be significant. The footprint isdirectly related to the size of the structure. Thisrelationship is in marked contrast to pilesupported and anchored structures where thefootpr int i s typ ica l ly smal l and i s notnecessarily a direct function of the size of thestructure.

Size reduction is typically the first designconsideration for mitigating the impact ofthese types of structures. Design alternativesthat can achieve a reduced footprint are thosethat incorporate piles or other reduced footingsto support the structure. Interestingly, recentupgrades to seismic construction standardshave required that piles be incorporated as partof the overall design to increase the stabilityof the structure in the event of an earthquake.Such is the case with bridge abutments; fill

pads are now being replaced by pile-basedfoundations. In the instance of foundation fillsand concrete structures, due considerationmust be afforded to design alternatives thatincorporate piles and other reduced footingsto decrease the footprint of the structure.

4.3.2.2 Materials

Consideration of material alternatives for fill,revetment and slab structures is dependentupon design alternatives that can incorporateother material types. Rip rap revetments maybe replaced by steel sheet pile to significantlydecrease the footprint of the revetment. Thecost of a steel sheet pile structure, however,is substantially greater than that of a rip rapstructure. As a result, for small revetmentprojects, the cost effectiveness of rip rap maypreclude the use of steel sheet pile.

For breakwaters, the feasibility of designalternatives will partial ly depend on theprevailing energy regime of the site affectedby proposed works. A floating breakwater,constructed of floating materials such as logs,barges or concrete pontoons, can be costeffective for partially protected sites where thewave heights to be dissipated are modest. Afloating breakwater has a substantially smallerfootprint than a rip rap breakwater. A re-duction in footprint can also be achievedthrough breakwater design that incorporatesa vertical wall constructed of a single row ofpiles. Where timber piles are considered,however, they would likely be treated andtherefore would introduce wood preservativesinto the aquatic environment. Introducingtoxins into the aquat ic envi ronment i sstrongly discouraged. Care must always betaken not to substitute one undesirable designoption with another.

4.3.2.3 Location

The most effective impact mitigation for fill,revetment and slab structures is to locate thesestructures outside of foreshore and nearshoresubtidal environments. The consideration ofsuch designs must also include potentialimpacts on fish and wildlife resources both


offshore and landward of these environments.In all instances, the design of a structure mustseek to minimize the use of fill, revetmentand slab design components.

Where design constraints demand the locationof a slab structure be within the foreshore ornearshore subtidal environment, such as a boatramp, the des ign of the s tructure mustconsider impacts to physical processes typicallyassociated with shorelines. The structure mustachieve a design that does not significantlyalter the prevailing current, wave and driftregimes. Structures have the potential to alterrates of flushing, material accretion, erosionand other processes. Such changes to physicalprocesses can impact both onsite and offsitefish and wildlife habitats.

4.3.2.4 Roughness

Increasing the roughness of fill, revetment andslab structures has its greatest benefits withinhigh salinity brackish and salt water habitats.Fill structures constructed of rip rap, such asbreakwaters, are in essence an artificial reef.They provide s imi lar s t ructura l habitatfeatures to those present in natural reefs. Not-withstanding engineering considerations, thesize of rock used for breakwaters can bemodified to benefit target species. The largerthe diameter of the rock, the larger the voidswithin the structure. Larger voids providerefugia for larger reef inhabitants, such aslingcod, while smaller voids provide refugiafor smaller reef inhabitants, such as coonstripeshrimp.

Concrete slab structures within high salinitybrackish and salt water environments can bemodified to enhance their ability to sustainproductive encrusting communities. Thevertical sides of slabs are typically flat. Theydeflect wave energy in several directionswithout significantly reducing it. The energyof the waves, and the log debris that oftenoccurs within coastal environments, scour theface of these structures, significantly reducingthe v igour o f encrus t ing communit i e s .Incorporating recesses in the vertical face ofslab structures provides encrusting organisms

with habitat adequate ly protected fromexcessive scour.

For all salinity regimes, rip rap revetments canbe modified to sustain a variety of productivehabitat features. Benches are one of the moste f f e c t i ve o f the se f e a ture s . They a r e astructural extension of the revetment. Thesurface elevation of the bench is dependenton the habitat type to be created. Highelevation benches, typically above the meanhigh water mark, are created to sustain acommunity of shrubs and small trees. Midelevat ion benches, located at e levat ionsbetween the mean high and low water marks,are created to sustain intertidal communitiesr ang ing f rom g rave l / cobb l e bed s o fmacroalgae to stands of marsh vegetation(Figure 4.17). Low elevation benches, frommean low water to several metres belowlowest low water, are created to sustain bedsof submergent vegetation. For mid-to-lowelevation benches, careful consideration mustbe afforded to the prevailing energy regimeand the potential for log debris accumulation;high energy and debris accumulation cansignificantly hamper the productivity ofhab i t a t benche s . Wi th c a r e fu l de s i gncons ide r a t ion , r ip r ap benche s c ansignificantly enhance the functional value ofrevetments to fish and wildlife. Chapter 5provides further detail regarding the designof benches.

Figure 4.17 Marsh bench within rip rap revetmentshortly after planting, Ladner Reach, Fraser River.

41

5Dikes

5.1 Introduction

Dikes are inherently located within the transition zone ofaquatic and terrestrial environments. This zone sustains someof the most productive fish and wildlife habitats in BritishColumbia. As dikes are often many kilometres long, they canhave a profound impact on the functional capacity of thesehabitats to support fish and wildlife, as is evident in the legacyof largely irreversible habitat losses attributable to major dikinginitiatives of the past. Such initiatives were focused strictly onland reclamation and did not consider impacts on fish andwildlife habitats.

While the era of large-scale dike construction is over, fish andwildlife habitat conservation remains a critical issue in thedevelopment of new dikes, modification of existing structures,and dike maintenance. Habitat conservation can be achievedwith the application of an integrated and interdisciplinarydesign approach that accounts for prospective impacts to fishand wildlife habitats and incorporates features that mitigatesuch impacts to the fullest extent practical. In this regard, someprogress has occurred over the past two decades through thecollaborative efforts of environmental and diking agencies.However, many dike design criteria and maintenance protocolscontinue to emphasize sterile, minimally vegetated structuresthat contribute little to the goal of habitat conservation.

Chapter 5 provides environmental design criteria for dikeconstruction and maintenance initiatives, with a clear focuson the consideration of approaches and features compatiblewith the primary function of diking, that of flood protection.Conventional structural design criteria essential for floodprotection are discussed, followed by the presentation ofinnovative environmental design criteria regarding the locationand alignment of dikes, the establishment of vegetationfeatures, and dike maintenance.


5.2 Structural Design

Trad i t iona l d ike de s ign cons ide ra t ionsinclude:

• flow, tide and wave regimes;• channel shape and configuration;• available construction materials

such as appropriate fill and rip rap;• bank conditions at the site, prior

to construction;• space limitations; and• upland uses.

Dikes are designed and constructed to preventflooding of low lying lands during floodevents. Dikes can be damaged by currents,wave s and f l ood ing . Acco rd ing l y, animportant component of dike design is themaintenance of the integrity of the dike.Generally, the structural elements of dikesinclude:

• a dike shoulder set at an adequateelevation to prevent overtoppingduring a design flood event;

• gentle grades on both the watersideand landside slopes; and

• bank protection on the waterwardslope to prevent erosion of the dikematerial and undercutting of thetoe and face of the dike.

The structural integrity of the dike can beimpacted by seepage and piping. Seepage isthe movement of water from the interior ofthe dike to its exterior. Points of dischargeare known as seeps. Excessive seepage cancause localized slope failure. The retentionof water due to the lack of adequate drainageof the soils within a dike can also lead tosaturated slopes and subsequent large-scalefailure. Piping is an erosion process in whichwater retrogresses through a seepage path,such as a decayed root conduit, forming ahole that increases in size with flow. Pipingdischarge occurs at the surface through seeps.

Design features that address seepage and pipinginclude:

• impermeable or low permeabilitycores to prevent through-flow ofwater; and

• a permeable sur f i c i a l l ayer tofac i l i t a te dra inage , therebyminimizing saturation of substrates.

5.2.1 Design Flood Conditions

To es t imate c re s t e l eva t ions and bankprotection requirements for riverine dikes, ananalysis of design flows should be undertaken.A range of flows, up to and including thedesign flow event, should be estimated, andwater surface profiles corresponding to the de-sign flows should be used to develop suitablecrest elevations. For ocean facing dikes, a waterlevel analysis, consisting of an assessment ofthe effects of storm surge, tides, wave and windsetup is required. A stability analysis of the dikerevetment must be carr ied out , and anevaluation of wave runup and overtoppingunder storm events should also be considered.

The Inspector of Dikes Office of the provincialMinistry of Sustainable Resource Managementsets Flood Construction Levels (FCL) in orderto f loodproof upland developments to acommon standard and to achieve an acceptablelevel of risk. The FCL is the lowest allowableelevation for the ground floor of an occupiedbuilding.

The FCL is equal to either the:

• 200 year maximum daily water levelplus 0.6 m of freeboard; or

• 200 year maximum instantaneouswater level plus 0.3 m of freeboard.

The highest level for a particular site becomesthe FCL.

Des ign cons idera t ions may inc lude anevaluation of proposed and/or existing uplanduse. Industrial facil ities, trailer parks orrecreational areas may be able to withstand agrea te r r i sk o f f looding than would a

Chapter 5 - Dikes Page 43

residential area. For areas accommodating suchland uses, the Inspector of Dikes Office mayre lax the FCL. Other genera l des ignconsiderations are associated with freeboardallowance and seismic requirements.

5.2.2 Diking Standards

Dikes are most frequently constructed orupgraded by a local, provincial or federalauthority. As such, structures often follow apre-set configuration or standard. For example,the standard dike design utilized in the 1968Fraser River Flood Control Program (FRFCP)employed the following design criteria:

• minimum crest width of 3.6 m,with crest material consisting of 150mm of crushed gravel;

• horizontal width of the filter andarmour layers of erosion protectionnot included as part of the crestwidth;

• minimum crest elevation at 1894flood adjusted level, plus a 0.6 mallowance for freeboard;

• maximum waterside dike slopes of3.0H:1.0V and 1.5H:1.0V for non-armoured and armoured dikes ,respectively;

• typica l lands ide dike s lopes of3.0H:1.0V;

• allowances for toe drains and otherdrainage features to facilitate freedrainage of the dike body;

• for non-armoured dike slopes, 150mm thick layer of topsoil hydro-seeded with grass seed; and

• for armoured dike slopes, an armourlayer thickness of 900 mm, with afilter layer thickness of 300 mm.

The application and width of armoured toeaprons was site specific. Figure 5.1 illustratesa typical FRFCP standard dike in section view.

For lands near the delta front of the estuary,an Acce le ra ted Dik ing Program wasimplemented as a result of flood damagessusta ined dur ing extreme high t ides in

December, 1982. The following damaged dikeswere repaired or reconstructed:

• Mud Bay;• Colebrook;• Serpentine and Nicomekl rivers;• Westham Island; and• Crescent Beach.

An agricultural design standard was adoptedfor this program that deviated from the designstandard typically implemented by the FRFCP.The outstanding design features of thisstandard are:

• a reduced crest width of 3.06 m;• waterside and landside slopes of

2.0H:1.0V;• a reduced freeboard of 0.3 m; and• an armoured toe apron 1.0 m in

width.

The waterside armouring standard varied fromdike to dike. The armouring on the dikes ofthe tidal portions of the Serpentine andNicomekl rivers consisted of rounded cobbles(Figure 5.2). The armouring on the Mud Bayand Westham Island dikes consisted of rip rap.Where rip rap was applied, it consisted of a500 mm thick armour layer with an underlying300 mm filter layer.

The construction of a dike along a river bankwill generally require some bank regrading.Steep or undercut banks may require regradingof the slope to 2.0H:1.0V or less. Dependingupon upland uses, bank sloping or grading maybe limited by the close proximity of utilities,buildings and/or roadways, costs associatedwith land acquisition, and/or the requirementto retain existing vegetation. In such situations,a slope of 1.8H:1.0V may be employed tolessen impacts on these resources.

Protection against erosion or scour of dikeslopes requires resistant materials. Resistancei s typ ica l ly prov ided by the mass andinterlocking nature of the materials. Structuralunits made of concrete or gabions may be used;however, within British Columbia, it is mosteconomical to use rip rap.


The reconstruction of dikes and revetmentsalso requires the careful selection and layeringof filter rock and other aggregates as beddingmaterials. These are sorted by size and layeredso that smaller sediments cannot be washedout through the interstices of larger rocks.Geotextile can also be used to prevent the lossof finer sediments through larger sized material.

Toe scour can seriously compromise thestructural integrity of dikes. To minimize toescour, toe aprons should be incorporated aspart of the dike’s overall armament. Duringconstruction, the placement of toe apronsinvolves the excavation of the base of dike andrevetment slopes and subsequent infill with riprap. A toe apron stabilizes the slope andprevents undercutting and slumping.

5.3 Environmental Design

5.3.1 Location

The primary function of dikes is to eliminatethe periodic flooding of land. The cause offlooding may be due to daily fluctuations intides, and/or to seasonal changes in water level.The majority of conventional riverine dikes inBritish Columbia were built along the naturalbanks of the main river channel (Figure 5.3).

Figure 5.1 Typical Fraser River Flood Control Program dike design.

3.6m

Structural Fill

1

1.5

1894 floodadjusted level plus0.6 m freeboardallowance

Elevation:

150mm ThickCrushed Gravel

900mm Thick Armour Layer

300mm Thick Filter Layer

Toe Open(Site Specific)

Figure 5.2 Nicomekl River estuary dike.

As a result, there has been a significant loss offloodplain woodlands and wetlands, as well asfloodplain distributary channels. Similarly, theconstruction of estuarine and marine dikes hasresulted in a significant loss of tidal marshesand swamps, with many tidal channels eitherlost entirely or converted to drainage canals.

Impacts to natural landscape features can bemitigated through dike location and alignment.Setback dikes are the most desirable designoption (Figures 5.4, 5.5 and 5.6). Ideally, thedike location and alignment is setback from themain river channel to avoid the majority of the


floodplain, or is setback beyond the high watermark for frequent flood or tidal events. Thesesetbacks often cannot be achieved due to con-flicting land uses, especially within developedareas. Regardless, the objective is to maximizethe distance of the setback so as the functionalcapacity of the affected area as habitat for fishand wildlife is maintained.

From an engineering perspective, setback dikesminimize the impact on flood channels,thereby accommodating conveyance andstorage during extreme flood events. Althoughexamples of setback dikes are rare, it is quitelikely that construction and maintenance costsof such dikes, relative to the conventional dikedesign, are decreased due to the position of thedike, lower dike fill volume and lack of expo-

sure to constant erosive forces. Erosionprotection for the setback dike is a designoption that is dependant upon overbank flowve loc i t i e s dur ing a f lood event . Bankprotection may also be implemented in thechannel, separate from the dike structure itself.

5.3.2 Vegetation

Vegetation can be incorporated into the overalldesign of a dike without compromising floodprotection. Often, the basic design of the dikedoes not need to be modified to accommodatevegetat ion; in other ins tances , a s l ightmodification in the basic design permits theincorpora t ion o f a r e l a t ive ly complexvegetation community.

Figure 5.3 Non-setback riverine dike.

Dike

River

high water level

low water level

Figure 5.4 Setback dike.

Riparian Woodland Retained

Dike

River

low water level

high water level


5.3.2.1 Shallow Slope Treatment

For sha l low s lopes ( e .g . d ike s lopes a t3.0H:1.0V), the incorporation of vegetation,in particular, herbs, grasses and small shrubs,offers long-term protection against surficiale ro s i on and p rov ide s s ome deg r e e o fprotection (primarily woody species) againstshallow mass-movement. Surficial erosion isminimized by vegetation through:

Interception - foliage, organic debris andhumus dissipate rainfall energy and preventthe compaction of soil by rain drops;

Restraint - root systems physically bind orrestrain soil particles while surficial organicdebris and humus filter sediments out ofrunoff;

Retardation - the surface roughness providedby organic debris and humus s lows thevelocity of surface runoff;

Infi l trat ion - roots , organic debris andhumus contr ibute to so i l poros i ty andpermeability; and

Transp i r a t i on - t h e d ep l e t i on o f s o i lmois ture by p lants de lays the onset o fsaturation and subsequent surface runoff.

A list of shrub species appropriate, from anecological perspective, for use on dike slopesis provided by Table 5.1. These species willalso not compromise the structural integrityof dike structures. The list reflects speciesthat express high vigour in an environmentthat is characterized by: a fluctuating waterlevel regime; little, if any, shade due to theabsence of trees; and, non-native soils usedto cons t ruct the d ike tha t a re poor innutrients and have a limited capacity to retainmoisture.

These species perform best when planted asclose to the wetted edge as natural conditionswill allow, typically in the range of 0.0 to 2.0m (vertical) above the frequent or normal highwater level; more drought tolerant species areappropriate for the uppermost portions of the

dike slope where drying of the soils occursduring the summer months. Taxonomic andecological descriptions for those speciespresented in the table and other speciessuitable for riparian and foreshore plantingprograms are presented in Appendix C.

Overbuilt (Figure 5.7) dikes can be shapedto enhance t opog r aph i c v a r i ab i l i t y,improving both the aesthetic qualities and thefunctional capacity of the dike as habitat forfish and wildlife. However, overbuilt dikeshave limited applications because they havea l a r g e r f oo tp r in t on th e l and s c ape ,

Figure 5.5 Setback riverine dike, Coquitlam River.

Figure 5.6 Setback riverine dike, Serpentine River.

Recent upgrade of the dike maintained the setbackfrom the original dike alignment; important shore-line habitats were retained.


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potentially impacting productive fish andwildlife habitat and thereby offsetting anyenvironmental benefits associated with theirunconventional design.

5.3.2.2 Ecopocket Treatment

The intent of ecopocket p lant ing i s toestablish vegetation intermittently within thearmour layer of the dike. Structures are oftenincorporated to form the ecopocket withinthe rip rap treatment while still maintaining

the structural integrity of the armament.The s e s t ru c tu r e s may con s i s t o f s t e e lcylinders, such as corrugated steel pipe, orcylinders constructed of reinforcing steel (i.e.‘ rebar baskets’ ) . Concrete pipe, such asmanhole casing, is an alternative pocketstructure. Non-woven geofabric may beutilized to line the pockets to retain fill soil.It is important that the structural integrityof the rip rap remain; it is often necessary tohave the structures extend through the armourlayer.


In the absence of structures, pockets may beconstructed in an overburden of rip rap onthe face of the slope (Figures 5.8 and 5.9).The additional rock forms the pocket. Thepocket is lined with non-woven geofabric.Fil l soil types and surface elevations aredependant upon design plant species.

5.4.2.3 Bench Treatment

The rip rap revetment of a dike can bemodified to incorporate a bench. The benchis a structural extension of the revetment. Asde s c r ibed in Chap t e r 4 , the sub s t r a t eelevation of the bench is dependent on theplant community to be established. The mostcommon application of benches is associatedwith the establishment of marsh vegetationon the lower slope of the dike. Figure 5.9displays the application of a relatively widebench design, while Figure 5.10 presents thetypical bench design.

5.4 Maintenance

A prudent and regular schedule of dikeinspection and maintenance is typical lyimplemented to identify and upgrade dikesthat have deteriorated. Inspections duringperiods of high f low are carr ied out tomonitor the performance of the dikes anddetermine if any sections are failing.

Dike maintenance can include:

• dike upgrading;• vegetation management;• dike slope repairs;• bank protection repairs; and• removal of grounded debris.

5.4.1 Dike Upgrading

5.4.1.1 Freeboard Improvements toExisting Dikes

The freeboard of an existing dike can beincreased by adding structural materials to thecrest of the dike, inside the outer face of thestructure. The freeboard increase provides anadditional factor of safety against flooding

Figure 5.7 Overbuilt dike.

Planted RiparianShrub Assemblage

high water levelGrowing Medium

Rip Rap Armour Layer

Filter Layers low water level

Figure 5.8 Overburden rip rap pocket.

Planted SmallShrubs

GrowingMedium

Filter Layer

Filter Fabric

Rip RapBerm


Filter Fabric


and overtopping. Working inside the outerface of the dike minimizes impacts to theenvironment.

5.5.1.2 Setback of Existing Dikes

Habitat enhancements and flood protectionimprovements can be achieved where riversidedikes currently exist. These dikes can be setback from the channel to provide additionalconveyance areas during flood events andprovide landscaping opportunities for therestoration and enhancement of riparianhabitats.

5.4.2 Vegetation Management

As part of the design of dikes, it is prudent toincorporate vegetation to minimize the erosionof surficial material. Shrubs and trees oftenbecome e s tab l i shed on d ike s lopes .Conventional dike management practicesdictate the removal of all woody vegetation ondike slopes, regardless of species. The basis ofthis management approach is that:

• extensive coverage by shrubs andtrees on slopes obscures and limitsvisibility of the slope and toe duringdike inspections; this can result infailure to detect evidence of erosion,animal burrows and/or the sloughing

Figure 5.10 Typical bench design.

Planted Marsh Vegetation

Rip RapContainmentBerm


Filter Layer

Filter Fabric

GrowingMedium

Figure 5.9 Ecopocket (inset: individual ecopocket) and bench treatments, Deas Slough, Main Arm distributarychannel, Fraser River.


of rip rap that may contribute todike failure during a flood event;

• large trees can pose a threat tostability during a flood event, as thedike soils become saturated and there su l t ing lo s s o f cohes ioncontributes to uprooting and thefalling of trees; this typically resultsin the displacement of material dueto upheaval of the root ball, and cancontribute to further erosion and/orstructural failure; and

• large trees are susceptible to windfallduring storm events; again, theupheava l o f the root ba l l cancontr ibute to e ros ion and/orstructural failure.

Trees are typically removed from dike slopesat an early age prior to the development ofan elaborate and massive root system. Theroot systems often die, and as they are not asignificant structural feature of the dike slope,their death and subsequent decompositiondoes not have a significant impact on theintegrity of the slope.

Shrubs hinder the conventional protocolemployed for dike inspections as they concealthe l ower s l ope f rom worke r s dur inginspections conducted from the crest of thedike. In those instances where the water bodyis navigable, inspections can be conductedfrom the waterward side of the dike, avoidingthe need to remove shrub vegetation tofacilitate visual inspection.

Unfortunately, dike maintenance programsoften do not discriminate between woodyvegetation that does and does not obscure andlimit visibility (from the landward side of thedike) or threaten the structural integrity of ad ike . Sh rub communi t i e s tha t su s t a insignificant fish and wildlife habitat values,and pose l i t t l e threat to the success fu lmaintenance of dike structures, are typicallyremoved. Maintenance programs must includecr i te r i a to determine the threa t o f theprevailing vegetation community to successfuldike maintenance. Once the threat is defined,an appropriate maintenance protocol should

be developed that mitigates, to the fullestextent practical, impacts to existing fish andwildlife habitat values. A critical componentof adequate impact mitigation is the abilityof maintenance personnel to identify woodyplant species.

Vegetation management of dikes can beimproved through the incorporation of somebasic ecological principles. Maintaining adense cover of vegetation, such as grasses andsmall shrubs, prevents the ready establishmentof trees. Maintenance may simply require thephysical removal of the relatively few treesaplings that do become established. In thoseinstances where large trees are selectivelyremoved as a measure to protect the dike, theexposed substrates beneath the previouscanopy should be seeded or planted withgrasses or shrubs, respectively. Integratedvegetation management, where the ecology ofplant species is exploited, is a long term main-tenance approach that is more economicallysustainable than the short term approachcharacterized by nonselective mowing andcutting.

5.4.3 Slope and Bank ProtectionRepairs

Traditionally, repairs to the dike slope havegenerally consisted of regrading the surfaceand then revegetating the bank, typically withherbs and grasses through hydroseeding. Bankprotection works have typically involved thereplacement and/or realignment of rock thathas been lost and/or moved, respectively,during a flood or storm event.

Where appropriate, the planting of shrubsshould be incorporated as part of the repairplan, regardless of whether or not shrubs werepart of the previous slope. Environmentallyresponsible dike maintenance protocolsconsider the enhancement of natural landscapefeatures for fish and wildlife.

Repair usually commences with the assessmentof damage and determination of the cause ofdamage. Remedial works are designed andsubmitted to regulatory agencies for review


and subsequent approvals. Works involvingthe regrading of slopes and the handling ofrip rap typically require heavy machinery. Thepotential for impacts to surrounding naturalf e a tu re s i s h i gh . Acco rd ing l y, s e ve r a lprecautionary measures should be taken tomitigate the impact of construction activitieson the environment.

Schedule repairs to minimize the risk oferosion:

• conduct repairs during dry weatherto avoid rain associated degradationof the work site; and

• complete repairs from early springto early summer to permit rapidestablishment of vegetation.

In scheduling repairs, the work program mustaccount for scheduling restrictions for inwater works associated with crit ical l i fehistory stages of juvenile and adult salmonids.Local Fisheries and Oceans Canada (DFO)personne l can prov ide such schedul ingrestrictions for their areas.

Implement cons t ruc t ion p rac t i c e s tomin imize d i s tu rbance and conta insediments:

• isolate the access areas for heavymachinery;

• provide working pads or surfaces(e.g. quarry tai l ings) for heavymachinery;

• cove r t empora ry so i l f i l l s o rs tockp i l e s w i th po lye thy l enesheeting or tarps; and

• enclose the downslope perimeter ofthe work s i te with s i l t fencingdur ing ex t ended ons i t econstruction.

Implement a pre-designed comprehensiverevegetation plan:

• prescribe a landscape treatment,including specifications for plantspecies, size and spacings, prior tocommencement of construction;

• where feasible, salvage sod andshrubs for replanting once repairsare completed;

• use mulches and other organicstabilizers to minimize erosion untilvegetation is established; and

• complete seeding and planting atleast one month prior to the end ofthe growing season.

Comprehensive revegetation plans addressbo th f l ood p ro t e c t ion and hab i t a tconservation design objectives. Collaborationbetween dike maintenance agencies and DFO,whereby information is exchanged regardinga l t e rna t i ve r evege ta t ion opt ions , i s animportant component of the maintenanceprocess.

53

6Establishing

Vegetation

6.1 Introduction

Native riparian and foreshore vegetation assemblages sustainimportant life history functions for fish and wildlife. As such,the potential impacts of shoreline development projects on theseassemblages are a key consideration during project review. Toadequately offset impacts to native vegetation assemblages, thedevelopment proponent is typically required by regulatoryagencies to conduct landscape works that establish nativevegetation. The successful establishment of vegetation isdependent upon sound technical design criteria.

This chapter emphasizes a design philosophy that seeks to createthe best environment possible for establishing native vegetation.To ensure the successful establishment of vegetation, the samelevel of diligence that is afforded the design of conventionalstructures must be afforded the design of vegetation features.Although this chapter provides des ign cr i ter ia for theestablishment of vegetation, it must be understood that thedesign of vegetation features is a highly site specific endeavour,and that specific design criteria will apply to individual projects.

6.2 Site Preparation

Proper soils are a necessary precursor to project success. Wherepossible, soils salvaged from sites recently cleared as part of landdevelopment activities, which prior to clearing sustained anassemblage of native species similar to that proposed by thevegetation plan, should be utilized. Soils salvaged from thesesites should be those that occurred within the upper rootinghorizon of the cleared vegetation and should not includesubsoils. Soils of the upper horizon contain organic constituents,such as decomposing leaf litter and wood, that complex the soil,afford proper drainage, and slowly release nutrients. They oftencontain the seed bank of desired vegetation, thereby facilitating


the natura l e s tab l i shment o f des i rab levegetation and the natural succession of species.

Sa lvaged nat ive so i l s conta in a d iver seassemblage of decomposers (Figure 6.1). Ofthese organisms, mycorrhizal fungi may be ofgreatest impor tance to plants . Throughinteractions with the roots of plants, thesefungi assist in the uptake of nutrients andwater, re s i s tance to some di seases , andal leviat ion of s t ress due to extremes intemperature and moisture. The importance ofmycorrhizal fungi for the establishment of newplantings has been recognized to the extent thatsome landscape contractors offer, as a service,the inoculation of imported topsoils withfungi.

If commercially produced topsoils are to beused, the soils must be free of constructiondebris (e.g. crushed bricks, glass, metal, etc.)and wood waste (e.g. hog fuel). The soilsshould be a mix of sand, silt, clay and organics,the proportions of which are dependent on thespecies to be planted. Table 6.1 presents general

criteria for constituents of soils intended foruse in terrestrial plantings.

In general, larger shrubs and trees require lessorganics than herbs, grasses and smaller shrubs.Further, some plants thrive in relatively acidicsoil conditions. Soil acidity may be increasedthrough addition of wood residuals and/or peatmoss. Wood residuals should be limited to firor hemlock sawdust. Cedar sawdust should notbe used. Peat moss should be of a horticulturalgrade, with 95 to 100 percent and 0 to 15percent of the particles passing through a 9.5mm and 500 um standard sieve, respectively.

When soils require additives to increasenitrogen, phosphorous and/or potassiumconcentrat ions, i t i s recommended thatcomposted manure be utilized rather thanchemical fert i l izers . Composted manureprovides an ideal medium for soil microfaunaand fungi, important precursors for thedecomposition of organic matter and thesubsequent availability of nutrients. Thenutr i ent s a re s lowly re l ea sed into the

Figure 6.1 Native soils host a diverse assemblage of organisms that greatly facilitate the decomposition of organic matter.Decomposers are consumed by both invertebrate and vertebrate animals. These animals are, in turn, preyed upon by otheranimals. The use of native soils can greatly enhance the ecology of the project location.

millipedehairy rove beetle

carpenter ant

sow bug

carabid beetle

soil protozoansmite

springtail

fungi and nematode

centipede

slug

earthworm

snail

Chapter 6 - Establishing Vegetation Page 55

environment during decomposition of themanure. Specifications for manure include:

• that it be free of harmful chemicals,such as any used to artificially hastendecomposition;

• that the particles in the manure passa 6.35 mm standard sieve; and,

• that it be relatively free of the viableseed of any plant species, with themaximum of two viable seeds perlitre of manure.

Criteria for soils for wetland herbs, rushes,sedges and grasses vary extensively accordingto species. As a result, a universal standard forwetland soils cannot be achieved. Typically, thesoils of desired vegetation, in proximity to theproject site, should be sampled and analyzedto develop project specific criteria.

Soil moisture is an extremely important designparameter for both riparian and foreshoreplanting programs. It is dependent on severalfactors, including soil type, topography andexposure to sunlight. The intrinsic capabilityof the soil to retain moisture is primarily

dependent upon the particle size of the mineralfraction and the overall content of organicmatter. Topography and exposure to sunlightare extrinsic factors that can dramatically influencesoil moisture.

Topography includes both the elevation(relative to surface and ground water) and slopeor grade. Within riparian environments, thesurface water elevation of adjacent rivers oftenextends well into adjacent riparian soils andinto the rooting horizon of riparian vegetation.Although riverine waters may not frequentlyflood the riparian environment, the prevailingwater level regime of the river can certainlyimpact, both negatively and positively, thevigour of riparian vegetation. Within tidalenvironments, the period of tidal inundation,which i s dependent on e l eva t ion , wi l ldetermine the extent and structure of theforeshore plant assemblage through both soilmoisture and the duration of inundation ofthe aboveground parts of plants. The slope orgrade of substrates determines the extent towhich water is retained within, or drainedfrom, the soil horizon.

Aspect is the orientation of the site relative tothe sun. Aspect changes with changes in slopeand direction of exposure. Project sites locatedon relatively steep north facing slopes mayrequire shade tolerant plants while, in contrast,sites on relatively steep south facing slopes mayrequire plants tolerant of full sunlight anddrought condit ions dur ing the summermonths.

S i t e s exposed to fu l l sun l ight shouldincorporate a deep soil horizon with relativelygentle slopes or grades. The deep soils providea mass that behaves somewhat as a reservoir;moisture i s reta ined within the rootinghorizon. Drainage is reduced by gentle grades,further enhancing retention of water.

A secondary design feature to reduce moistureloss is the incorporation of a light colouredmulch, such as hemlock or fir wood chips orpasture hay, to reduce heating of the soil bysunlight. Topsoils are relatively dark, readilyabsorbing solar energy. Evaporation of soil

Organic Content percent dry weight

10-30

Soil Property Percent Dry Weight of Mineral Fraction

Drainage

Texture

Particle Size Classes

Gravel greater than 2 mm 0-10less than 75 mm

Sanda greater than 0.05 mm 50-70less than 2 mm

Siltb greater than 0.002 mm 10-30less than 0.05 mm

Clayb less than 0.002 mm 10-20

Acidity pH

5.0-6.5

percolation should be such that standingwater is not visible 120 minutes after arain event of moderate to heavy intensityof at least 10 minutes.

Table 6.1 Riparian Soil Properties

apart ic le size sand: 95-100 percent pass through a 4.76 mm standard sieve0-40 percent pass through a 500 um standard sieve0-5 percent pass through a 53 um standard sieve

bsi l t and clay combined: maximum 40 percent


moisture is increased by heating. Light colouredmulches reflect sunlight, reducing the extentto which the soil is heated, and in turn, therate of evaporation.

While soils should never be permitted tocompletely dry, soils should also never bepermitted to experience prolonged periods ofsaturation. Prolonged saturation impactsplants within both foreshore and riparianenvironments; it limits the ability of the rootsof plants to respire, often leading to the deathof plants through ‘drowning’.

There is a misconception that wetland herbsand grasses require persistent saturated soilconditions, often with water perched abovesubstrate elevations. Persistent saturated soilconditions often result in the drowning ofmany common wetland plants. For example,t ida l marsh c rea t ion pro jec t s wi th insouthwestern British Columbia often seek toestablish Lyngby’s sedge (Carex lyngbyei) marsh(Figure 6.2). A primary design considerationin the creation of Lyngby’s sedge marshes isthe specification of substrate surface elevationsconsistent with those of native sedge marshesin proximity to the project site. Achievingaccurate substrate elevations, however, is onlyone component of proper site preparation.Adequate dra inage i s another c r i t i ca lcomponent. Some projects have been able toachieve only partial success in establishingLyngby’s sedge through neglect of this latterdesign consideration; substrates drain in-adequately, rendering the affected rootinghorizon relatively void of oxygen. These areasare markedly apparent by the lack of vegetation.

Soil moisture interacts with the intensity andduration of sunlight to determine the presenceand vigour of plants. This is especially pro-nounced for wetland vegetation. Wetlandvegetation is typically very intolerant of shade.Decreases in intensity and duration of sunlightinduce decreases in areal cover and biomass.Lyngby’s sedge and slough sedge (C. obnupta),two closely allied species, exemplify thisrelationship between shade and soil moisture(Figure 6.3). Riparian shrubs and trees oftenoverhang and shade tidal marshes. This shading

often precludes Lyngby’s sedge from growingat elevations that it would otherwise inhabit.In contra s t , s lough sedge thr ive s a sgroundcover beneath the same shrubs and trees.Careful consideration must be afforded thelight regime of the area to be planted withwetland vegetation.

6.3 Species Selection

In general, and in order of decreasing priority,species selected for planting programs shouldadhere to the following criteria.

Native species characteristic of naturalriparian and foreshore plant assemblages

Projects that incorporate a large area canoften sustain the majority of speciescharacteristic of natural assemblages.The ecological interactions of naturalsystems are complex. Accordingly,rather than specify individual speciesbased on their perceived value as fishand wildlife habitat, natural assemblagesof native species should be specified forplanting. For riparian woodlands, thisincludes many groundcover species inaddition to shrubs and trees.

Figure 6.2 Lyngby’s sedge marsh created immedi-ately downstream of No. 2 Road bridge, Middle Armdistributary channel, Fraser River.


Native species that dominate a componentof natural riparian and foreshore plantassemblages

Some projects, due to site constraints,do not allow for the establishment of anatural assemblage of native species. Insuch instances, the specified plant listshould at least be comprised of speciesthat dominate natural plant assemblagesin proximity to the project site. For ex-ample, for riparian projects that traversepower transmission line right-of-ways,there is a restriction as to the height ofmature shrubs and trees that can beplanted. The ultimate height permittedis dependent upon local topography andthe height of transmission lines abovethe ground. As a result, the plants thatcan be established are limited to herbs,rushes, sedges, grasses and shrubs thatat maturity do not exceed the height re-striction. Similarly, a size restriction isoften applicable to structures, such asdikes, that may be structurally compro-mised by large shrubs and trees.

Native species of exceptional vigour

Planting projects are often susceptibleto invasion by aggressive, non-nativeplant species that can quickly establisha monospecific (i.e. single species) coverover portions of the project site. Nota-b le spec ie s inc lude b lackberry(Rubus discolor and R. lacianatus) andJapanese knotweed (Polygonumcuspidatum) (Figures 6.4 and 6.5).Monospecific stands of non-nativeplant species within shoreline environ-ments can significantly limit the numberof habitat functions these environmentscan sustain for fish and wildlife.

The provision of food for fish and wild-life by monospecific stands, whetherdirectly provided by the plant (e.g.fruit) or indirectly as an organism thatfeeds upon portions of the plant (e.g.herbivorous and detrivorous insects), islimited by the temporal availability ofsuch food. For example, the productionof fruit by plants is limited to a spe-cific time of the year. As well, insects,particularly life stages, are also available

Exposed to direct sunlight, tidalinundation frequent, soilsconsistently near saturation

Lyngby’s Sedge(Carex lyngbyei)

Slough Sedge(Carex obnupta)

Often shaded, tidal inundationinfrequent, soils inconsistentlynear saturation

LitterCorridor

Figure 6.3 Relative sunlight, inundation and soil moisture regimes of Lyngby’s sedge and slough sedge.


as prey only during specific times of theyear. A diverse assemblage of plant spe-cies provides a diverse array of fooditems, both in terms of type and timeof availability.

To minimize the potential for invasionof the planting site by undesirable plantspecies, it is often necessary to focus theselection of native stock upon plant ma-terial that can withstand competitive in-teractions with such species. For thoseinstances where blackberry is prevalent,the size of the stock at the time of plant-ing often determines whether or not theplanted material can survive interactionswith blackberry.

Blackberry is notorious for smotheringplanted material; it readily utilizes manyshrubs and small trees as living trestles,quickly blanketing the plants with amatrix of vines and leaves (Figure 6.6).The size of the stock must be as large aspossible, with the species selected capa-ble of relatively vigorous growth. Slowgrowth is a liability; whatever advantageis gained over blackberry by plantinglarge stock would be quickly lost dueto the exceptional growth that is oftenexhibited by blackberry.

If the planting site encompasses, or isclose to, thickets of blackberry, theplanting plan must prescribe the clear-ing and grubbing of blackberry. Clear-ing and grubbing is conducted not onlyto minimize the vegetative expansioninto and within the planting site, butalso to minimize the recruitment ofblackberry seeds into the project site.The planting of shrubs and trees willfacilitate the recruitment of seeds ofmany species by providing new perch-ing sites for frugivorous birds. Duringthe fruiting period for blackberry, thedroppings of these birds will containthe seeds of blackberry. The number ofblackberry seeds within these droppingsis dependent upon the proximity ofblackberries to the perching site.

Japanese knotweed is an upright, shrub-like, herbaceous perennial that can growto over 3 metres in height. The stem isjointed, appearing somewhat bamboo-like. Japanese knotweed readily estab-lishes dense thickets within shorelineenvironments. The plant possesses longstout rhizomes that often form anelaborate and extensive undergroundnetwork within established stands. Asfor blackberry, any knotweed within orin proximity to the project site shouldbe cleared and grubbed. The seeds areof little foraging value to wildlife andare readily disseminated by water andwind. The dissemination of vegetativepropagules within garden and landscapemaintenance waste is also an important

Figure 6.4 Himalayan blackberry (Rubus discolor).

Figure 6.5 Japanese knotweed (Polygonumcuspidatum).


means of dispersal; knotweed is particu-larly prevalent within urban areas.

Where the prospect of colonization orpersistence of Japanese knotweed islikely, it is recommended that plantsspecified by the project design bethose highly adapted to the prevailinggrowing conditions of the project site.Japanese knotweed is extremely toler-ant of flooding, drought and salinity.Furthermore, it is recommended thatany shrubs specified by project designbe those that exhibit a multi-stemmedtu f t ed hab i t ( e . g . n ineba rk(Physocarpus capitatus)); such speciesare not likely to be extirpated throughspatial competition with knotweed.The rhizomes of knotweed simplycannot invade the primary root ball ofsuch plants. Native rhizomatous spe-cies, including the relatively aggressivesalmonberry (Rubus spectabilis), arereadi ly outcompeted for space byJapanese knotweed.

Where the project design includes theclearing and grubbing of non-nativeplants, such as blackberry and Japaneseknotweed, it is imperative that vegeta-tive material and soils containing bothvegetative fragments and seeds be dis-posed of in a manner and at a locationthat does not result in the propagationof new plants. Furthermore, with regardto the project site, monitoring shouldbe conducted to ensure that seedlings ornew shoots emerging from overlookedvegetative fragments are removed.

6.4 Plant Propagules andPlanting

The type of plant propagule ut i l ized i sdependent on the plant species selected,propagule availability, and the season in whichthe planting is to occur. Propagules may onlybe obtained from natural communities duringcertain times of the year due to the temporalnature of the availability and viability of many

propagule s . Thi s a l so app l i e s to non-containerized nursery stock, where the spadingof material from the field is often restrictedto the late fall, winter and early spring whenplant material is relatively dormant and the riskof inducing physiological shock in plantmaterial is minimized.

6.4.1 Shrubs and Trees

Propagule types o f woody vege ta t ioncommonly utilized in fish and wildlife habitatcreation projects include cuttings, transplantand nursery stock.

6.4.1.1 Cuttings

Nursery operations commonly use normal,heel and mallet cuttings to propagate plants(Figure 6.7). A normal cutting will root easilyfor the majority of riparian shrub species andis the type of cutting conventionally used toestablish plants in the field. For all types, thecutting must possess several nodes from whichnew shoots can develop.

Figure 6.6 Western redcedar ‘escaping’ Himalayanblackberry.


The number o f spec ie s tha t have beensuccessfully established in the field via cuttingshas been limited. Fish and wildlife habitatprojects have typically utilized normal cuttingsof willow (Salix spp.), poplar (Populus spp.)and red osier dogwood (Cornus stolonifera).Unfortunately, the majority of habitat projectsdo not incorporate contingencies for the trialof plant establishment techniques that utilizea variety of cutting types and plant species.Referencing cutting technology utilized bynursery operations, there is potential for anincrease in the diversity of cutting types andspecies utilized by habitat projects. Table 6.2lists common riparian plant species that havebeen successfully propagated by nurseriesutilizing cuttings, with species and cuttingtypes successfully established in the field byhabitat projects noted.

Normal cuttings are usually pruned stems orshoots without accessory features. Normalcuttings are the most desirable cutting for fishand wildlife habitat projects due to the relativeease with which they may be inserted into theground when utilized as live stakes. As withall cuttings, a pair of sharp shears is essentialfor making clean cuts. Dull shears bruise planttissues. Damaged tissues are more susceptibleto disease and rot, conditions that compromisethe viability of the cutting. The ends of the

clean cuttings typical ly cal lous, therebypreventing rot from reaching viable nodes.

Heel cuttings consist of young side shoots thatare stripped away from the main stem so thata thin sliver of bark and wood from the mainstem accompanies the shoot. The heel providesan additional barrier to rot.

Mallet cuttings are similar to heel cuttings, butincorporate more of the main stem than a heelcutting. Mallet cuttings should be taken fromnew stems late in the growing season. A cut ismade horizontally across the parent stemimmediately above a suitable side shoot. Thecut should be made as close to the side shootas pos s ib le to minimize d ie -back andsubsequent rot. A second horizontal cut ismade about 2 cm below the top cut so thatthe side shoot is isolated with a small ‘mallet’of the main stem.

The type of wood used for cuttings varies withdifferent plant species and the type of cuttingselected. Types are categorized according to theage of the wood and consist of softwood,greenwood, semi-ripe and hardwood.

Softwood is the most immature part of thestem and has the highest capacity to developroots. However, cuttings made of this wood

Figure 6.7 Three basic types of cutting commonly used for propagation.

normal heel mallet


type a l so exhibit the highest morta l i ty.Softwood cuttings are taken in the spring fromthe fast-growing tips of plants. They are verysusceptible to water loss through newlyemerged leaves. Even a small amount of waterloss will hinder root development. If leaves ona new cutting wilt, all root developmenttypically ceases and the cutting dies.

Greenwood cuttings are taken from the softtip of the stem after the spring flush of growthhas slowed. The cut stem is slightly harder and‘woodier’ than a softwood cutting. Greenwoodcuttings have a limited ability to develop roots.Cuttings should be taken early in the morningfrom a fully turgid stem. The cutting shouldbe immediately placed in a bucket of water or

polyethylene bag in a shaded location toprevent water loss.

Semi-ripe cuttings are those taken at the endof the growing season in late summer. Theyare thicker and harder than softwood cuttingsand are therefore more robust. They are stillsusceptible to the problems of water loss asthey still possess leaves. Semi-ripe cuttings canbe taken from a main stem or from the sideshoots. The tip of the stem should be removedif it is soft and fleshy; retain the tip if the apicalbud has hardened and growth has ceased forthe year.

Hardwood cuttings are the easiest and mostcommon cutting utilized in habitat projects.

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A hardwood cutting is made during thedormant season from the fully mature stem ofa deciduous shrub or tree. As there are no leavespresent , the potent ia l for water los s i sminimized. Hardwood cuttings may be takenat any time during the dormant season.

Normal and heel cuttings may be taken fromsoftwood, greenwood, semi-ripe and hardwoodstems. Mallet cuttings are restricted to semi-ripe and hardwood stems.

The application of rooting hormones tocuttings can enhance root development. Themost common and bes t su i t ed root inghormone is beta-indolyl-butyric acid (IBA).Softwoods and greenwoods are treated with0.2% IBA. Semi-ripe and hardwoods aretreated with 0.4% IBA.

Cuttings may be individually live-staked orincorporated as wattles. Cuttings must not beallowed to dry. It is preferable that they beused shortly after harvest from parent stock.If there is a delay between harvest and plantingthat could result in drying, cuttings should bestored in refrigeration compartments in thedark (to prevent shoot elongation) and in amoist condition.

Live-stakes should incorporate at least 4 nodesand be cut so that a node is within 2.5 cm ofthe top of the cutting (Figure 6.8). Cuttingsfrom 2.0 to 4.0 cm in diameter and 30 to 45cm in length are typically preferred for staking.

Live-stakes are planted with the bottom of thecutting in the ground. At least two nodesshould be entirely buried in the ground. Avoiddamaging or stripping the bark or bruising thestakes when planting. Within soft soils, thestakes may be driven in by hand or with awooden maul. An axe or heavy hammer shouldnot be used; considerable damage to thecutting will result. It may be necessary to setholes in the ground for the stakes (within wellconsolidated soils). In all instances, the soilsshould be firmly compressed against the stakesto minimize water loss. No more than 10 cmof the cutting should be exposed after planting.

Wattles consist of stems tied together as abundle (Figure 6.9). The minimum size of thecuttings is often dependent on the speciesselected, but in general, the diameter of thecuttings should not be below 1.25 cm. Thenumber of cuttings varies with the size andspecies of plant material. The cuttings areplaced within the bundle with the largestdiameter ends alternating. When compressedand tightly tied, the bundles should be 10 to15 cm in diameter and taper at each end (i.e.cigar shaped). Tying is accomplished by holdingand compressing the bundle with two or moreloops of binder’s twine or similar material. Tiesare placed 30-40 cm apart using non-slippingknots.

The wattles are placed within excavatedtrenches. The trench should be shallow, thedepth approximately 3/4 of the diameter ofthe wattle (Figure 6.9). The wattles are heldin place on the downhill side of the trenchesby anchor stakes that are driven through thebundles at a maximum spacing of 50 cm. Aminimum of two stakes should be used foreach bundle. A stake should always be placedat each bundle tie. The trenches are re-filledwith soil. All voids within and surrounding thewattle must be filled. The soils must be firmlypacked to prevent drying of the cuttings.

Anchor stakes may consist of several materialtypes . L ive-s takes are des i rable as theyultimately add plant cover. They are, however,easily damaged and are generally best appliedwithin unconsolidated soils. In most instances,stakes composed of dimension lumber are themost effective type.

Wattles have been increasingly utilized to top-dress the rock-armoured surfaces of riverbanks. The wattles may be tied directly torocks of the armour layer, or tied to a plasticor wire mesh that lies beneath the armourlayer. The wattles are configured as a grid,wi th both hor i zonta l and ver t i ca lcomponents. The interstices of the rocks arefilled with soil. Nursery grown sod is placedwithin each of the grid squares. The wattlesare partially buried in soil. Back channels,such a s tha t cons t ruc ted a t Sapper ton


Landing, Fraser River, are ideal candidates forthis treatment (Figure 6.10).

6.4.1.2 Nursery and Transplant Stock

Wherever possible, nursery stock should beutilized to establish natural assemblages ofnative species (see Figure 6.11 for types ofnursery stock). Furthermore, it is preferablethat nursery stock be propagated from seed andcuttings, with the collection of native plantsand subsequent incorporation into containersdiscouraged. Sources of native plant materialmay be obtained from the British ColumbiaLandscape & Nurser y Assoc iat ion. TheAssociation provides an annotated list of nativep lant s commerc ia l l y g rown in Br i t i shColumbia at www.canadanursery.com/bclna/native.shtml.

Transplants of native vegetation should beconsidered only when nursery stock is notavailable. Prospective donor sites should beassessed as to their capability to withstand theremoval of plants. Plant removal must notsignificantly alter the species membership orstructure (e.g. age, size, habit, etc.) of theassemblage.

Ideal donor sites, especially for shrub and treespecies, are those sites for which there ispending land development. Comprehensiveplanning, whereby plant material on pendingdevelopment sites is inventoried, facilitates theprocurement of donor material without undueimpacts on natural communities. Collectedmaterial may be stored and grown within anursery, where propagation utilizing a varietyof techniques could increase both the numberand size of the original material.

Bare root transplants (where shrubs and smalltrees are excavated, transported without nativesoil surrounding the root mass) should beperformed only during late winter, prior to theswelling of buds. Bare root stock should beplanted immediately after extraction. Theroots must be kept moist to minimize rootdeath. Bare root transplants are best conductedduring wet weather.

Figure 6.8 Live-stake with newly emerged shoots.

Figure 6.9 Willow wattles being installed alongthe bank of Derby Reach, Fraser River.


Balling and burlapping involves excavating alarge proportion of the root mass and associatedsoil and wrapping it in burlap cloth. It is bestperformed during late winter; it should not beperformed when the plants are in flower and/or during mid to late summer.

The balls (roots and soil) should be solid andwrapped tightly with 142 gram jute burlap.Balls up to 50 cm in diameter may be wrappedwithout the support of heavy twine or rope.Double burlap may be used on balls of 50-60cm in diameter in lieu of twine. Balls 60 cmand larger in diameter should be drum laced at20 cm spacing using 6 mm rope. In general,the root ball diameter should be at least tentimes the calliper of the shrub or tree, 50percent of the height of plants less than 1 min height, or 30 percent of the height of plants1 to 3 m in height.

It is critical that the ball is large enough toincorporate a high proportion of young roots.Too often, the old, woody portion of the rootmass is all that is incorporated in the ball. Thisresults in the delayed expansion of the rootmass into the new soil and/or the ultimatedeath of the plant.

Container stock is the ideal propagule typefor shrubs and trees. The damage to rootsassociated with either bare root transplants orba l l ing and bur lapping i s avo ided .Unfortunately, container sizes are typicallylimited to standard no.1, no.2 and no.3 sizes.Although large containers are available (e.g.no.15 size), large plants are often field grownfor later balling and burlapping.

6.4.2 Forbs, Rushes, Sedges andGrasses

To date, forbs, rushes, sedges and grasses havepredominantly been l imited to plantingprojects for wetland assemblages, such asmarsh, wet meadow and swamp. They havebeen typically omitted from projects withinnon-wetland riparian environments. Successfulintegration of all components of a natural plantassemblage, including non-woody species, is

key to achieving habitat functions importantto fish and wildlife.

Commonly used propagule types for non-woody plants are sprigs, rhizomes, tubers,plugs and sods, cuttings and seeds. Currently,there i s l imi ted s tock ava i l ab le f romcommercial nurseries, with transplant stockbeing the primary source of material forprojects with a limited time frame. Nurseriesare, however, capable of growing material forprojects (Figure 6.12) given sufficient notice(at least one growing season). Stock grown bycommercial nurseries is typically available asplugs of various sizes, 4 inch pots and no.1pots (Figure 6.13).

Figure 6.10 Wattle grid treatment within a con-structed tidal back channel at Sapperton Landing,Fraser River: wattle grid installed on surface of rockrevetment (top); and, infilling of grid squares withsoil and sod (bottom).


For those propagules that require extraction ofplant material from native donor sites, caremust be taken to minimize the impact on thedonor plant community. As the propagules aregenerally small in size, donor stock extractionshould be conducted manual ly, therebyavoiding impacts to the donor site typicallyassociated with heavy machinery. Materialshould be extracted at intervals that will allowfor quick re -e s tab l i shment o f cover byimpacted vegetation. The treatment of holesresulting from excavation is dependent on theenvironment from which the material is beingextracted. Within wetland environments, forhigh sedimentation regimes and/or looselyconsolidated soils, the holes may be simplycol lapsed us ing a l a rge d ibble ; for lowsed imenta t ion reg imes and/or f i rmlyconsolidated soils, the holes should be filledwith substrates suitable for the growth ofimpacted vegetation. Holes created withinupland environments should be filled with soiltypical of those soils in which the impactedvegetation is rooted.

6.4.2.1 Sprigs

A sprig is composed of a single stem andassociated roots, or a basal shoot and shortrhizome sections (Figure 6.14). Depending onthe species, it may be necessary to trim thestem so that the plant stands upright whenplanted. As the roots of many rhizomatousspecies are annual, old roots may be strippedfrom the stem and/or rhizome. Care shouldbe taken when handling new roots. New rootsare white or light in coloration. Old roots aredark and often exhibit tissue death and rot.Rhizomatous species of Carex, Scirpus andJuncus are the best candidates for sprigs.

6.4.2.2 Tubers and Rhizomes

Tubers and rh izomes a re undergroundperennial structures (Figure 6.14). Althoughroots often emerge from tubers and rhizomes,tubers and rhizomes are distinct from roots instructure and function. Both tubers andrhizomes are modified stem structures. Theyare primarily storage organs and often appearswollen. In contrast, roots are structures

Figure 6.11 Nursery and transplant stock types for shrubs and trees.

bare root ball and burlap container


separate from stems. They absorb water andnutrients from surrounding soils and conveythem to other parts of the plant. Roots areprimarily anchorage structure for above-groundparts.

Transplants of tubers and rhizomes should beperformed during late winter and early springwhen the plants are dormant or in the earlystages of growth. Viable propagules are lightlycoloured. Healthy tubers are hard while healthyrhizomes are somewhat elastic. Rhizomes maybe cut into sections that have identifiable nodes(often identified by a concentration of rootsat a single location). Species of Carex, Scirpusand Typha are excellent candidates for rhizomecuttings; the rhizomes are large, robust andeasily identifiable. Eleocharis and some speciesof Juncus possess small, relatively fragilerhizomes that are often damaged duringextraction and planting; these species shouldbe transplanted using sediment-root-rhizomeplugs. The morphology of tubers is dependenton the species. For example, viable skunkcabbage (Lysichiton americanum) tubers shouldinclude the apical bud and tuber. Viable Typhatubers should possess at least two nodes toensure shoot elongation in the spring.

6.4.2.3 Plugs and Sods

Plugs and sods are composed of stems, roots,tubers and/or rhizomes , and assoc iated

substrates. A common device for extractingplugs of marsh vegetation is a golf green cupcutter that extracts a cylindrical plug 10 cm indiameter and 20 cm in length (Figure 6.15).Plugs may also be extracted using a largedibble. Sod size is variable depending on themethod of extraction and mode of transport.Sod may be extracted using spades or other sodcutting devices.

The majority of forbs, rushes, sedges andgrasses can be transplanted as plugs and sods.For tufted species, such as soft rush (Juncuseffusus), woolly bulrush (Scirpus cyperinus) andarrowgrass (Triglochin maritimum), the size ofthe plug or sod consists of the entire plant.Plant species characterized by large, robustrhizomes and tubers, such as skunk cabbageand Typha, are inappropriate for transplant asthe plug or sod often incorporates only a partof the viable belowground structure; damageto such structures often results in plant death.

6.4.2.4 Cuttings

Cuttings are clipped, above-ground vegetativematerial that are taken off species that naturallyroot from stem nodes. Cuttings are often rakedinto the substrate of the project site. Goodcandidate s for cut t ings a re p ick leweed(Salicornia virginica) and bentgrass (Agrostisspp.).

Figure 6.12 Native plant nurseries are well preparedto grow native forbs, rushes, sedges and grasses forprojects.

Figure 6.13 Planting no.1 pot Lyngby’s sedge atBurnaby Big Bend, North Arm distributary channel,Fraser River (inset: sedge with pot removed).


6.4.2.5 Seeds

To date, the primary focus of seeding has beento stabilize disturbed and exposed soils of apro jec t s i t e . Often , non-nat ive c lover s(Trifolium spp.) and a mix of native and non-native grasses comprise the majority of the seedmix applied to a site. Although seeds of nativeplant species are readi ly avai lable f romcommercial suppliers, seeding to establish adesired assemblage of non-woody species hasrarely been conducted.

Where soil stabilization is a priority, seeds ofdesired species may be used to augment thestabilization mix. The species selected shouldpossess seeds that germinate readily. The speciesshould be those that can maintain a footholdamongst the stabilization species. The focusshould be on tu f ted and aggre s s ivestoloniferous and rhizomatous species. Biennialand perennial species should be prioritized.

In seeding wetland environments, care mustbe taken to seed during drawdowns that exposewetland substrates for a period sufficient toachieve germination and substantial root andshoot elongation. The substrates must remainsaturated. The seeds should be gently rakedinto the soil. Flooding prior to germinationwill result in a significant loss of seed due to

f lo ta t ion . The f looding and comple tesubmergence of young shoots will result inconsiderable mortality due to drowning.Vegetation establishment within wetlandenvironments utilizing seeds requires theability to manipulate water levels and monitorseed germination and plant growth during theinitial establishment period.

For those environments above normal highwater, the success of seeding i s great lyimproved when mulch is used. If the mulch isapplied prior to seeding, the seeds should be

small-fruited bulrush sprig skunk cabbage tuber cattail tuber and rhizome

Figure 6.14 Examples of common propagule types for marsh plants.

Figure 6.15 Extracting Lyngby’s sedge plug fromdonor marsh using golf green cup cutters (inset: cupcutter plugs of sedge).


gently raked into the mulch. Seeding is bestapplied in conjunction with the application ofmulch. The mulch adheres to the soil, holdingthe seed in place until germination.

6.5 Maintenance

Maintenance is a key component of anyp lant ing program. For most pro jec t s ,maintenance typically consists of the irrigationof mater i a l p lanted wi th in up landenvironments and the removal of undesirablenon-native species within all environments.During the initial growing season, irrigationmay be required every two to three days.Undesirable plant species should be removedearly in the growing season when individualsare small and easy to remove. The duration ofthe maintenance program is project specific andshould include the initial growing season.Extended plant maintenance, lasting for severalgrowing seasons, facilitates the successfulestablishment of a natural assemblage of nativeplant species.

Appendix A - Glossary Page A-1

The following terms are defined in the context of their use by the main body of this publication.

acclimatize to habituate to new environmental conditions, such as juvenile salmon when theyhabituate to brackish and salt water upon entering the lower reaches of an estuary

ambient that which is freely surrounding, such as water that is not bound within soil ororganisms

aspect the direction of exposure

bathymetry physical relief features or the surface configuration of the ocean bottom or someother large body of water

biennial a plant that lives for two growing seasons or years, germinating, growing and storingfood reserves in below ground structures during the first year, and flowering andsetting seed during the second year; biennials are herbaceous

biophysical that which is living and non-living, as it relates to the traits or characteristics of aspecific environment

bog an acidic wetland characterized by Sphagnum peat

brackish with reference to water characterized by salinities substantially below that of seawater, ranging from greater than 0.5 to approximately 17 parts per thousand; alsowith reference to environments, and the organisms and communities inhabitingthese environments, characterized by such water

bulkhead an engineered structure, such as a sheet pile wall, that retains fill within a shorelineenvironment

compensation measures taken, such as the creation of new habitat or the enhancement of existinghabitat, to offset residual impacts (i.e. where mitigation does not offset all negativeimpacts) to habitat caused by shoreline development

conveyance the act of conveying or transporting water flows

coppice to grow new stems from a recently cut stump

detritus particulate material composed of organic matter (i.e. dead plant and animal matter)and decomposer organisms such as fungi and bacteria

diffusion the spreading, scattering or distribution of light

distributary with reference to a channel that conveys part of the flows of another, such as thosechannels that convey the flows of the main channel of a river through a delta

Appendix A:Glossary

Page A-2 Shoreline Structures Environmental Design

ectone transition zone between two structurally different communities

estuary a semi-enclosed body of water, which has an open connection to the ocean, whereat its seaward margin sea water is measurably diluted by fresh water derived fromland drainage, and at its landward margin water levels are measurably altered bytides

fen an acidic wetland characterized by sedge peat; a typical feature is a low gradientstream or pond that slowly conveys surface flows through the wetland

fetch a wave generated by wind

floodplain level lowland along the margins of the hydraulic channel(s) of a stream or river ontowhich water flows during flood stage

foreshore the area along the shoreline between low water and high water elevations; low waterand high water elevations are a function of tides and/or seasonal water levels withina stream or river

fresh with reference to water characterized by salinities no greater than 0.5 parts perthousand; also with reference to environments, and organisms and communitiesinhabiting these environments, characterized by such water

intertidal pertaining to that area along the shoreline between low tide and high tide waterelevations

inundation flooding or submergence; the act of causing an object to be beneath the surface ofwater

marsh a wetland that is typically characterized by shallow water and by emergent aquaticplants such as cattail, sedges, rushes and grasses

media soil; organic and inorganic material suitable for the planting of vegetation

mitigation measures taken to minimize impacts to habitat caused by shoreline development,such as the replacement of fill with piles to reduce the footprint of a structure

monospecific of a single species, such as a tidal marsh comprised entirely of Lyngby’s sedge(Carex lyngbyei)

mycorrhizal fungi fungi in association with the roots of vascular plants; such fungi break down com-pounds to basic components, such as nitrogen and phosphorous, that can bereadily absorbed by vascular plants; in turn, carbohydrates, synthesized by vascularplants, are absorbed by the fungi

nearshore in close to proximity to the shoreline, either from water or land

pan natural shallow depression containing water or mud; within salt and brackish environ-ments, the evaporation of water creates hypersaline conditions

percolation the process by which water flows through the interstices of substrates

Appendix A - Glossary Page A-3

perennial a plant that lives for more than two growing seasons or years

permeable porous; capable of passing water

pier an engineered structure that projects out into a body of water, typically at 90° to theshoreline

propagules part of a plant, such as a cutting or seed, that can give rise to a new individual plant

revetment engineered protection of a slope

riparian within and in close proximity to the hydraulic channel of a stream or river

rip rap angular rock

salt with reference to water characterized by salinities approaching those of sea water,from greater than 17 to 30 parts per thousand; also with reference to environments,and the organisms and communities that inhabit these environments, characterizedby such water

salt wedge a layer of salt water that lies beneath a layer of fresh water within the lower reachesof an estuary; the separation of the two layers persists as the fresh water is sub-stantially less dense than the salt water and the water column is not sufficientlymixed by wave and tidal action; the salt water layer decreases in depth with increas-ing distance from the ocean due to the increasing elevation of the channel bottom,with the upstream point defined by an intercept with the bottom; the salt wedgemoves downstream and upstream within the distributary channels of an estuary withoutgoing and incoming tides, respectively

saturation at which point a soil or other medium can not receive or store more water

seismic with reference to earthquakes

strata structural layers, such as those defined by distinct substrates of sediments or thosedefined by canopy, subcanopy and groundcover of a woodland

subtidal pertaining to that area of the shoreline below the low tide elevation

swamp a wetland that is typically characterized by saturated soils and by shrubs and treestolerant of saturated soils and periodic inundation

transplant the extraction plant material, its transport, and subsequent planting from one loca-tion to another

wake a wave generated by watercraft

Page A-4 Shoreline Structures Environmental Design

Appendix B - Bibliography and Photographic Credits Page B-1

Appendix B:Bibliography and

Photographic CreditsChapter 1

B1.1 Photographic Credits

Chapter Cover Mark A. AdamsPage 2 Figure 1.1 Prov ince o f Br i t i shColumbia

Chapter 2

B.2.1 Bibliography

Adams, M.A., and G.L. Williams. in press. Chapter 14:Tidal Marshes of the Fraser River Estuary: Composition,Structure and a History of Marsh Creation Efforts to 1997in Fraser River Delta: Issues of an Urbanized Estuary.Geological Survey of Canada, Vancouver, BC.

Hart, J.L. 1973. Pacific Fishes of Canada. Fisheries ResearchBoard of Canada. Bulletin 180. 740p.

Hourston, A.S., H. Rosenthal and H. von Westernhagen.1984. Viable hatch from eggs of Pacific herring (Clupeaharengus pallasi) deposited at different intensities on avariety of substrates. Canadian Technical Report of Fisheriesand Aquatic Sciences No.1274. 19p.

Phillips, R.C. 1984. The ecology of eelgrass meadows inthe Pacific Northwest: A community profile. U.S. Fishand Wildlife Service. FWS/OBS-84/24. 85p.

Seliskar, D.M., and J.L. Gallagher. 1983. The ecology oftidal marshes of the Pacific Northwest coast: a communityprofile. U.S. Fish and Wildlife Service. FWS/OBS-82/32.65p.

Williams, G.L. 1989. Coastal/Estuarine Fish HabitatDescription and Assessment Manual. Part 1 - Species/Habitat Outlines. Prepared by G.L. Williams and AssociatesLtd., Coquitlam, BC. Prepared for Supply and ServicesCanada, Hull, QU. 129p.

Ricketts, E.F., J. Calvin, J.W. Hedgpeth and D.W. Phillips.1985. Between Pacif ic Tides . 5th Edit ion. StanfordUniversity Press. Stanford, CA. 652p.

Kozloff, E.M. Seashore Life of the Northern Pacific Coast.1973. University of Washington Press. Seattle, WA. 370p.

B.2.2 Photographic Credits

Chapter Cover Mark A. AdamsPage 6 Figure 2.1 Mark A. AdamsPage 9 Figure 2.3 Mark A. Adams

Figure 2.4 Mark A. AdamsPage 10 Figure 2.5 Otto E. LangerPage 11 Figure 2.7 Rick HarboPage 14 Figure 2.9 Mark A. Adams

Figure 2.10 Mark A. AdamsPage 15 Habitat Partitioning:

Yellow Headed BlackbirdHabitat Canadian Wildlife ServiceBird R. Wayne CampbellNest John M. Cooper

Red-winged BlackbirdHabitat Mark A. AdamsBird R. Wayne CampbellNest R. Wayne Campbell

Brewer’s BlackbirdHabitat Mark A. AdamsBird R. Wayne CampbellNest R. Wayne Campbell

Page 16 Figure 2.11 Eric D. BeaubienFigure 2.12 Scott Barrett

Chapter 3

B.3.1 Bibliography

Adams, M.A. and K.E. Asp. 2000. Habitat and DevelopmentClassification System – User’s Manual and Map Sheets‘Courtney River Estuary Management Plan’. Prepared byECL Envirowest Consultants Limited, New Westminster, BC.Prepared for Fisheries and Oceans Canada, Nanaimo, BC.9p + maps. www-heb.pac.dfo-mpo.gc.ca/english/cremp/.

Fisher ies and Oceans Canada. 1986. Policy for theManagement of Fish Habitat. Fisheries and Oceans Canada,Ottawa, ON. 30 p. www-heb.pac.dfo-mpo.gc.ca/english/publications.htm.

Fisheries and Oceans Canada. 1995. Directive on theIssuance of Subsection 35(2) Authorizations. Fisheries andOceans Canada, Ottawa, ON. 6p. www.dfo-mpo.gc.ca/habitat/publications_e.htm.

Page B-2 Shoreline Structures Environmental Design

B.3.1 Bibliography contd

Fisheries and Oceans Canada. 1998. Habitat Conservationand Protection Guidelines. Second Edition. Fisheries andOceans Canada, Ottawa, ON. 20p. www-heb.pac.dfo-mpo.gc.ca/english/publications.htm.

Fisheries and Oceans Canada. 1998. Decision Frameworkfor the Determination and Authorization of HarmfulAlteration, Disruption or Destruction of Fish Habitat.Fisheries and Oceans Canada, Ottawa, ON. 22p. www.dfo-mpo.gc.ca/habitat/publications_e.htm.

Water and Land Use Committee . 1994. An EstuaryManagement Plan for the Fraser River. Fraser River EstuaryManagement Program, New Westminster, BC. 113p.

www3.ec.gc.ca/EnviroRegs

www.archaeology.gov.bc.ca

www.bc-land-assets.com/water/

www.bieapfremp.org

www.ceaa-acee.gc.ca

www.dfo-mpo.gc.ca/habitat/

www.eao.gov.bc.ca

www.gov.bc.ca/wlap/

www.pacific.ccg-gcc.gc.ca/nwp/

www.pyr.ec.gc.ca

apps.icompasscanada.com/lrc/


Chapter Cover Mark A. Adams

Chapter 4

B.4.1 Bibliography

Hutton, K.E. and S.C. Samis. 2000. Guidelines to protectfish and fish habitat from treated wood used in aquaticenvironments in the Pacific Region. Canadian TechnicalReport of Fisheries and Aquatic Sciences 2314. 34p. www-heb.pac.dfo-mpo.gc.ca/english/publications.htm.

Witherspoon, B., and R. Rawlings. 1994. Shoreline AccessDesign Guidelines for Washington Marine ShorelineHabitats . Unpublished Manuscript. Washington StateDepartment of Natural Resources, Olympia, WA. 58p.

Anonymous. 1995. Marina Development Guidelines for theProtect ion of F i sh and Fish Habitat . Unpubl i shedManuscript. Fisheries and Oceans Canada, Vancouver, BCand BC Ministry of Environment, Lands and Parks, Victoria,BC. 66p . www-heb .pac .d fo -mpo .gc . c a / eng l i sh /publications.htm.

Sharpe and Diamond Landscape Architecture. 1997. AccessNear Aquatic Areas: A Guide to Sensitive Planning, Designand Management. Fisheries and Oceans Canada, Vancouver,BC and BC Ministry of Environment, Lands and Parks,Surrey, BC. 82p. www-heb.pac.dfo-mpo.gc.ca/english/publications.htm.

Western Wood Preservers Institute and Canadian Instituteof Treated Wood. 1997. Best Management Practices forthe Use of Treated Wood in Aquatic Environments .Unpubl i shed Manuscr ipt . Western Wood Preser ver sInstitute, Vancouver, WA. 35p. www.wwpinstitute.org.

Sinnott, T.J. 2000. Assessment of the Risks to AquaticLife from the Use of Pressure Treated Wood in Water.Unpublished Manuscript. Division of Fish, Wildlife andMar ine Resource s , New York Sta t e Depar tment o fEnvironmental Conservation. 45p. www.dec.state.ny.us/website/dfwmr/habitat/hoa1b3.htm.


Chapter Cover Mark A. AdamsPage 30 Figure 4.1 Mark A. Adams

Figure 4.2 Mark A. AdamsFigure 4.3 Mark A. Adams

Page 31 Figure 4.4 Mark A. Adamsinset Otto E. Langer

Figure 4.5 Fraser River Port AuthorityFigure 4.6 Otto E. LangerFigure 4.7 Gary L. Williams

Page 35 Figure 4.12 Mark A. AdamsPage 37 Figure 4.15 Robert CochranePage 39 Figure 4.17 Mark A. Adams

Chapter 5

B.5.1 Bibliography

Anonymous. 2000. Riprap Design and Construction Guide.BC Ministry of Environment, Lands and Parks, WaterManagement Branch, Victoria, BC. 19p + appendix.

Anonymous . 1999 . Env i ronmenta l Guide l ine s fo rVegetation Management on Flood Protection Works toProtect Public Safety and the Environment. Fisheries andOceans Canada , Vancouve r, BC. , BC Min i s t r y o fEnvironment, Lands and Parks, Victoria, BC. 19p.

Appendix B - Bibliography and Photographic Credits Page B-3

B.5.1 Bibliography contd

Anonymous. 1994. Memorandum of Agreement for theWashington State Departments of Fisheries, Wildlife, andEcology and the United States Army Corps of Engineersconcerning Vegetation and Habitat Management on FloodControl Structures . Department of the Army, SeattleDistrict, Corps of Engineers, Seattle, WA.

Anonymous . undated . Is sues Regard ing Vegeta t ionManagement on Levee Embankments. REMR TechnicalNote EI-M-1.4. US Army Engineer Waterways ExperimentStation, Vicksburg, MS.

Chillibeck, B., G. Chislett and G. Norris. 1992. LandDevelopment Guidelines for the Protection of AquaticHabitat. Fisheries and Oceans Canada, Vancouver, BC andBC Ministry of Environment, Lands and Parks, Victoria,BC. 128p . www-heb .pac .d fo -mpo .gc . c a / eng l i sh /publications.htm.

Johnson, A.W. and J.M. Stypula. 1993. Guidelines for BankStabilization Projects in the Riverine Environments of KingCounty. King County Department of Public Works, SurfaceWate r Management Div i s ion , S ea t t l e , WA.dnr.metrokc.gov/wlr/biostabl/.


Chapter Cover Mark A. AdamsPage 44 Figure 5.2 Mark A. AdamsPage 46 Figure 5.5 Kon Johansen

Figure 5.6 Rolf W. SickmullerPage 49 Figure 5.9 Mark A. Adams

inset Mark A. Adams

Chapter 6

B.6.1 Bibliography

Adams, M.A. , and I .W. Whyte . 1990. Fish HabitatEnhancement: A Manual for Freshwater, Estuarine andMarine Habitats. Fisheries and Oceans Canada, Vancouver,BC. DFO 4474. 330p.

Anonymous . unda ted . Northwes t Nat i ve P l ant s -Identification and Propagation. King County Departmentof Public Works, Surface Water Management Division,Seattle, WA. 37p + appendices.

Browse, P.M. 1988. Plant Propagation. Simon and Schuster,Inc., Toronto, ON. 96p.

Link, R. 1999. Landscaping for Wildlife in the PacificNorthwest. University of Washington Press, Seattle, WA.320p.

MacDonald, B. 1989. Practical Woody Plant Propagationfor Nursery Growers. Timber Press, Portland, OR. 669p.

Vanbianchi, R., M. Stevens, T. Sullivan and S. Hashisaki.1994. A Citizen’s Guide to Wetland Restoration. Adopt aBeach. Seattle, WA. 71p.


Chapter Cover Mark A. AdamsPage 56 Figure 6.2 Mark A. AdamsPage 58 Figure 6.4 Mark A. Adams

Figure 6.5 Mark A. AdamsPage 59 Figure 6.6 Mark A. AdamsPage 60 Figure 6.7 Mark A. AdamsPage 63 Figure 6.8 Mark A. Adams

Figure 6.9 Myles HargrovePage 64 Figure 6.10

top Mark A. Adamsinset John Grindon

bottom John Grindoninset Mark A. Adams

Page 65 Figure 6.11left Mark A. Adamsmiddle Bruce Peelright Mark A. Adams

Page 66 Figure 6.12 Mark A. AdamsFigure 6.13 Mark A. Adams

inset Mark A. AdamsPage 67 Figure 6.14 Mark A. Adams

Figure 6.15 Mark A. Adamsinset Mark A. Adams

Appendix C

B.C.1 Bibliography

Alaback , P. , J . Antos , T. Goward , K. Ler t zman, A .MacKinnon, J. Pojar, R. Pojar, A. Reed, N. Turner and D.Vitt. 1994. Plants of Coastal British Columbia . BCMinistry of Forests. J. Pojar and A. MacKinnon (Eds.).Lone Star Publishing, Vancouver, BC. 526p.

Brayshaw, T.C. 1976. Catkin Bearing Plants (Amentiferae)of British Columbia. Occasional Papers of the BritishColumbia Provincial Museum No.18. Province of BritishColumbia, Victoria, BC. 176p.

Cooke, S.S. (ed.). 1997. A Field Guide to the CommonWetland Plants of Western Washington and NorthwesternOregon. Seattle Audubon Society, Seattle, WA. 417p.

Correll, D.S. and H.B. Correll. 1975. Aquatic and WetlandPlants of Southwestern United States. 2 Volumes. StanfordUniversity Press, Stanford, CA. 1777p.

Page B-4 Shoreline Structures Environmental Design

Farrar, J.L. 1995. Trees in Canada. Canadian Forest Service.Fitzhenry and Whiteside Limited, Markham, ON. 502p.

Hitchcock, C.L., A. Cronquist, M. Ownbey and J.W.Thompson. 1969. Vascular Plants of the Pacific Northwest.5 Volumes. University of Washington Press, Seattle, WA.

Klinka, K., V.J. Krajina, A. Ceska and A.M. Scagel. 1989.Indicator Plants of Coastal British Columbia. BC Ministryof Forests. University of British Columbia Press, Vancouver,BC. 288p.

Weinmann, F., M. Boule, K. Brunner, J. Malek and V.Yoshino. 1984. Wetland Plants of the Pacific Northwest.U.S. Army Corps of Engineers, Seattle District, Seattle,WA. 85p.

B.C.2 Photographic Credits

Mark A. Adams with the exception of photographs providedby Art McLeod, as follows:Pages B-9; B-26; B-32 (female cone); B-33 (female cone);B-35 (catkins); B-38; B-48 (berries); and, B-50.

Appendix C - Common Wetland and Riparian Plants Page C-1

IntroductionThe intent of this appendix is to familiarize the reader with common wetland and riparian plants that arefrequently used by habitat mitigation and compensation projects. This presentation does not attempt toidentify and describe all the plants that occur within coastal wetland and riparian environments, but ratherintroduce to the reader plants that are characteristic of these environments.

The taxonomy utilized is based on Hitchcock et al. (1969). Changes to the scientific names of plants sincethis publication are presented below.

Osmaronia cerasiformis = Oemleria cerasiformisPopulus trichocarpa = Populus balsamifera var. trichocarpaPyrus fusca = Malus fuscaSalix lasiandra = Salix lucida var. lasiandraScirpus acutus = Schoenoplectus acutusScirpus americanus = Schoenoplectus pungens var. longispicatusScirpus cyperinus var. brachypodus = Scirpus atrocinctusScirpus maritimus var. paludosus = Bolboschoenus maritimus var. paludosusScirpus validus = Schoenoplectus tabernaemontaniTriglochin maritimum = Triglochin maritima

The majority of definitions presented in the glossary of plant terms, and the majority of the descriptorspresented in the species summaries, including illustrations, are based on Hitchcock et al.

Glossary of Plant Termsacuminate gradually and concavely tapered to a narrow tip or sharp point

adventitious any root or shoot arising from a stem that otherwise would not be expected (e.g. rootsand shoots that emerge as a result of burial of the stem)

anthesis the period when a flower is fully expanded and functional

apical at the apex of the tip

auricle a small projecting lobe or appendage such as at the base of the petiole or blade

awn a slender bristle

bract a reduced or modified leaf associated with a flower or an inflorescence; it is not part ofthe flower or inflorescence

bractlet a small bract; a bract that is borne on a petiole rather than subtending it

callus the firm, thickened base of the lemma

calyx the sepals of a flower, collectively

capsule a dry dehiscent fruit composed of more than 1 carpel

carpel a fertile leaf bearing undeveloped seed(s)

Appendix C:Common Wetland

and Riparian Plants

Page C-2 Shoreline Structures Environmental Design

catkin a dense compact or elongated inflorescence bearing many small naked or apetalousflowers

channeled marked with one or more deep, longitudinal grooves

cone a cluster of fertile leaves or associated scales on an axis

cordate heart-shaped with a notch at the base

dehiscent opening at maturity to release or expose contents (e.g. seeds)

distal toward or at the tip, or at the furthest distance away

drupe a fleshy fruit that encloses a stony seed (e.g. cherries)

ellipsoid elliptic in longitudinal section and circular in cross section (3-dimensional descriptor)

emergent emerging or coming out from; typically with reference to marsh plants that emerge andstand above the water’s surface

flexuous displaying a zig-zag habit

fruit a ripened ovary, together with any other contiguous structures that ripen with it

glabrous smooth; without hairs or glands

glume one of a pair of bracts at the base of a grass spikelet that does not subtend the spikelet

habit the general appearance or manner of growth of a plant

heterophyllous displaying more than one shape of leaf

inflorescence a cluster or grouping of flowers

lacerate with an irregularly jagged margin

leader the terminal (i.e. top) shoot of a tree

leaf axil the point of the angle formed by the leaf or petiole with the stem

lemma one of the pair of bracts (lemma and palea) which generally subtends individual flowersin grass spikelets

lenticel a slightly raised area in the bark of a stem or root that displays a porous texture

lenticular shaped like a double convex lens

ligule the appendage on the inner (upper) side of the leaf at the junction of the blade andsheath of grasses

necrotic a plant organ displaying dead tissue

node the place on the stem to which leaves are, or have been, attached

obovate like ovate, but larger toward the distal end

obtuse blunt; with the sides coming together at an angle of more than 90°

ovate shaped like the longitudinal section through a hen’s egg (1-dimensional descriptor)


ovoid shaped like a hen’s egg (3-dimensional descriptor)

palea one of the pair of bracts (lemma and palea) which generally subtends individual flowersin grass spikelets

pedicel the stalk of a single flower in an inflorescence

peduncle the stalk of an inflorescence or of a solitary flower

perianth the sepals and petals of a flower collectively

perigynium a special bract that encloses the achene in Carex

petal a member of the internal set of floral leaves that are usually white or colored

petiole a leaf stalk

pith spongy tissue in the centre of the stem or trunk of some woody plants

prostrate flat on the ground

pubescent bearing small hairs

reticulate displaying a matrix or grid pattern

rhizome a creeping underground stem

rhombic having the figure of a rhomb, a quadrilateral figure whose sides are equal and oppositesides parallel, as in a diamond (3-dimensional descriptor)

scabrous rough to the touch, due to the structure of the epidermis or to the presence of short,stiff hairs

scale any small, thin or flat structure

sepal a member of the external set of floral leaves that are usually greenish and more or lessleafy in texture

septum a partition within the hollow leaf or stem of some aquatic and emergent plants (pl. septa)

sessile attached directly by the base, without a stalk, such as a leaf without a petiole or aflower without a pedicel

spike/spikelet a more or less elongated unbranched inflorescence with sessile or subsessile flowers

stipule one of a pair of basal appendages found on many leaves

stolon an elongated, creeping stem on the surface of the ground

stoma a minute opening in the epidermis of leaves through which water vapour passes (pl.stomata)

style slender stalk which typically connects the stigma to the ovary

tepal a sepal or petal, or a member of an undifferentiated perianth

trigonous with three angles

whorl a ring of 3 or more similar structures radiating from a node or common point


Plant List

Scientific Name Common Name Page

Herbs Carex aquatilis Water Sedge C-6

Carex sitchensis Sitka Sedge C-6

Carex lyngbyei Lyngby’s Sedge C-7

Carex obnupta Slough Sedge C-8

Carex rostrata Beaked Sedge C-9

Scirpus acutus Hardstem Bulrush C-10

Scirpus validus Softstem Bulrush C-10

Scirpus americanus American Threesquare C-12

Scirpus cyperinus Woolly Bulrush C-13

Scirpus maritimus Saltmarsh Bulrush C-14

Scirpus microcarpus Small-fruited Bulrush C-15

Eleocharis palustris Creeping Spike Rush C-16

Juncus articulatus Jointed Rush C-17

Juncus balticus Baltic Rush C-18

Juncus effusus Soft Rush C-19

Agrostis stolonifera Creeping Bentgrass C-20

Agrostis exarata Spike Bentgrass C-20

Glyceria elata Tall Mannagrass C-22

Glyceria grandis Reed Mannagrass C-22

Phalaris arundinacea Reed Canary Grass C-24

Calamagrostis canadensis Bluejoint Reedgrass C-25

Distichlis spicata Saltgrass C-26

Salicornia virginica Perennial Pickleweed C-27

Salicornia europaea Annual Pickleweed C-27

Triglochin maritimum Seaside Arrowgrass C-28

Typha latifolia Broadleaved Cattail C-29

Shrubs and Acer circinatum Vine Maple C-30Trees

Acer macrophyllum Broadleaf Maple C-31

Alnus rubra Red Alder C-32


Scientific Name Common Name Page

Shrubs and Betula papyrifera Paper Birch C-33Trees contd

Cornus stolonifera Red Osier Dogwood C-34

Corylus cornuta Beaked Hazelnut C-35

Crataegus douglasii Black Hawthorn C-36

Lonicera involucrata Black Twinberry C-37

Osmaronia cerasiformis Indian Plum C-38

Physocarpus capitatus Pacific Ninebark C-39

Picea sitchensis Sitka Spruce C-40

Pinus contorta var. contorta Shore Pine C-41

Populus trichocarpa Black Cottonwood C-42

Prunus emarginata Bitter Cherry C-43

Pseudotsuga menziesii Douglas fir C-44

Pyrus fusca Pacific Crabapple C-45

Rhamnus purshiana Cascara C-46

Rosa nutkana Nootka Rose C-47

Rubus parviflorus Thimbleberry C-48

Rubus spectabilis Salmonberry C-49

Salix hookeriana Hooker’s Willow C-50

Salix piperi Piper’s Willow C-50

Salix lasiandra Pacific Willow C-52

Salix scouleriana Scouler’s Willow C-53

Salix sitchensis Sitka Willow C-54

Sambucus racemosa Red Elderberry C-55

Sorbus sitchensis Sitka Mountain Ash C-56

Sorbus scopulina Western Mountain Ash C-56

Sorbus aucuparia European Mountain Ash C-56

Spiraea douglasii Hardhack C-58

Symphoricarpos albus Snowberry C-59

Thuja plicata Western Redcedar C-60

Tsuga heterophylla Western Hemlock C-61


Carex aquatilisC. sitchensisSCIENTIFIC NAME

Water SedgeSitka SedgeCOMMON NAME

Water sedge is characterized by 30 to 100 cmlong stems borne singly or few together on stout,well developed rhizomes. The leaves are flat, longand 2 to 7 mm in width. Sitka sedge is similar towater sedge; it has coarser, stouter and moredensely clustered stems. Rhizomes are short orabsent with stems up to 2 m in length. The leavesare up to 1 cm in width.

The inflorescence of water sedge is characterizedby 3 to 7 well spaced, cylindrical spikes, 1.5 to 5cm in length. The terminal spike is typically male,while the other spikes are either entirely female orboth male (upper portion) and female (lowerportion). All the spikes are sessile or nearly so.The bracts subtend the terminal spike, the lowestone elongate and leaf-like, ranging in length from 7to 25 cm. The perigynium is elliptic to obovate,more or less strongly flattened, with welldeveloped marginal nerves. It is 2 to 3.3 mm inlength, including the short (0.1-0.3 mm) beak.Each perigynium is accompanied by a scalereddish-brown to purplish-black in colour with apale midrib. The scale is generally narrower andminutely shorter to longer than the perigynium.The lenticular achene is 1.2 to 1.5 mm in length; itis distinctly shorter and typically narrower than theperigynial cavity.

Sitka sedge displays 2 to 3 terminal male spikes.In comparison to water sedge, the spikes aremore elongate and range from 3 to 10 cm inlength. The spikes, in particular the lower ones,are generally more or less nodding on slenderpeduncles that range from 3 to 10 cm in length.

Both water sedge and Sitka sedge commonlyoccur within fens, shrub swamps and tidal andnon-tidal fresh marshes. They can withstandlonger periods of inundation than most other Carexof fresh marshes; as a result, it may be foundalong the margins of sloughs as near-monospecific stands. Within non-tidal freshmarshes, common community associates includebeaked sedge, bluejoint reedgrass and reedcanary grass.

inflorescencefor Sitkasedge

inflorescencefor watersedge female

spike

male spike

perigynium

C. aquatilis


habit

male spike

perigynium

female spike

Carex lyngbyeiSCIENTIFIC NAME

Lyngby’s SedgeCOMMON NAME

The 15 to 100 cm tall stems emerge singly or insmall clusters from well developed creeping

rhizomes. The leaves are flat, mostly 2 to 6 mm inwidth, and are typically shorter than the stem.

The upper 1 to 2 floral spikes are male, while thelower 2 to 6 spikes are entirely female or part

male (upper portion) and female (lower portion).The upper spikes are somewhat erect, being

borne on short peduncles, while lower spikes,borne on long peduncles, typically droop or nod.

The perigynium is elliptic to elliptic-ovate (egg-shaped), leathery and thick-walled with prominentnerves along its margins and somewhat obscurenerves on its faces; it is 2.2 to 3.5 mm in length,

with 2 stigmas emerging from its small beak. Thelenticular achene is 1.6 to 2.2 mm in length. Light

to dark brown sharp tipped scales, with a palemidrib, are narrower and longer than the perigynia.

Lyngby’s sedge is often the dominant species oftidal low salinity brackish and fresh marshes. It

often occurs as expansive near-monospecificstands. Within low salinity brackish environments,common community associates include American

three-square, Baltic rush, saltmarsh bulrush andseaside arrowgrass. Within fresh environments,

common community associates include softstembulrush, hardstem bulrush, creeping spike rush,

jointed rush, creeping bentgrass and broadleavedcattail. A common associate within near-

monospecific stands is lilaeopsis (Lilaeopsisoccidentalis); this diminutive plant occurs

within the ‘understory’ of suchstands. Lyngby’s sedge

occurs throughout coastalBritish Columbia.

Due to its high net annual production of biomass(per unit area), and its tendency to be a dominant

species within estuarine environments, it isconsidered to be a critical component of the

productive capacity of these environments for fishand wildlife.


Carex obnuptaSCIENTIFIC NAME

Slough SedgeCOMMON NAME

The general habit of the plant is as dense tufts ofstems 60 to 150 cm in length. The coarse, firmleaves are flat or channelized, 3 to 10 mm in widthand shorter than the stems. The plant possesseslong, stout, creeping rhizomes.

The upper 1 to 3 floral spikes are male, while thelower 2 to 5 spikes are entirely female or partmale (upper portion) and female (lower portion).The spikes are sessile or borne on shortpeduncles. The perigynium is elliptic, leathery andthick walled with prominent nerves along itsmargins and without nerves on its faces; it is 2.4to 3.1 mm in length, with 2 stigmas emerging fromits small beak. The lenticular achene is 1.9 to 2.4mm in length and almost fills the perigynium.Purplish-black sharp tipped scales, each with apale midrib, extend beyond the perigynia.

Slough sedge is common within mid to highelevation tidal fresh marshes and shallow non-tidalfresh marshes. It is a conspicuous groundcoverwithin tidal and non-tidal fresh swamps. It occursoccasionally within low salinity brackish tidalswamps where inundation is infrequent. Incontrast to many other wetland species, it isevergreen, retaining the majority of its leavesthrough the winter. Slough sedge occurs withincoastal British Columbia south of latitude 55° N.

Common community associates within freshmarshes include small-fruited bulrush, woollybulrush, bluejoint reedgrass, reed canary grass,beaked sedge and other sedge species. Acommon community associate within freshswamps is small-fruited bulrush.

perigynium

achene

habit

female spike


Carex rostrataSCIENTIFIC NAME

Beaked SedgeCOMMON NAME

The stems, 50 to 120 cm in height, arise singly oras clusters from stout, elongate creeping

rhizomes. Leaves are distributed along the entirelength of the stem; the upper leaves often extend

beyond the height of the stem. The leaves arerobust, distinctively yellowish-green, generally flat

(often with a channel at the base) and up to 12mm in width.

The upper 2 to 4 male floral spikes are 2 to 6 cmin length, with the upper and lower spikes

peduncled and sessile, respectively. The lower 2to 5 female floral spikes are 2 to 10 cm in lengthand up to 1.5 cm in width, cylindrical to oblong,

sessile or nearly so. Intermediate spikesoccasionally sustain both male (upper portion) and

female (lower portion) flowers. The trigonousachene, 1.3 to 2 mm in length, is contained within

an inflated, elliptic-ovate (egg-shaped),membraned perigynium 4 to 7 mm in length, the

end abruptly contracted into a conspicuous beak.The style is persistent, bony, becoming strongly

flexuous or contorted as the achene matures.Three (3) stigmas append the style. The achenes

are accompanied by brown scales that aretypically both shorter and narrower than the

achenes.

This sedge does not occur within tidal salt orbrackish marshes. It is, however, one of the most

common sedges of fresh marshes in BritishColumbia. It often occurs within tidal fresh

marshes as expansive, near-monospecific stands.It occupies the mid to high elevations of these

marshes. Beaked sedge is common within freshmarshes of lake margins and low elevation bogs. It

also occurs within the most saturated portions ofwet meadows. Except for the Queen CharlotteIslands, it occurs throughout British Columbia.

Common community associates within freshmarshes include water sedge, slough sedge,

bluejoint reedgrass, reed canary grass andbroadleaved cattail. Within wet meadows,

common community associates include reedcanary grass, creeping bentgrass, woolly bulrush,

small-fruited bulrush and soft rush.

perigynium

habit

femalespike

achenes withinperigynia


scale

spikelet

acheneswith bristles

Scirpus acutusS. validusSCIENTIFIC NAMES

Hardstem BulrushSoftstem BulrushCOMMON NAMES

Both hardstem bulrush and softstem bulrushattain heights of 1 to 3 m. The plants arecharacterized by large woody rhizomes and roundstems that measure 1 to 3 cm in diameter at thebase. The common names refer to the ease withwhich one can crush the stem between one’sfingers. The leaves are reduced and are restrictedto the base of the plants.

Terminal clusters of approximately 10 spikeletsare borne on short and long peduncles onhardstem and softstem bulrush, respectively; theinflorescence of hardstem bulrush is morecompact than that of softstem bulrush. Thespikelets of hardstem bulrush are longer (8 to 15mm) than those of softstem bulrush (to 10 mm). Anarrow bract 3 to 4 cm in length subtends theinflorescence in both species.

The achenes of both species are approximately 2to 2.5 mm in length. They are elliptic-ovate (egg-shaped) and have a distinct point (stylar apiculus).Bristles, emerging from the base of the achenes,are equal to or exceed the length of the achene.The achenes are wrapped by brownish to greyishscales, completely in hardstem bulrush andpartially in softstem bulrush.

inflorescence

S. acutus

S. acutus


Both species occur within fresh marshes alongthe margins of lakes to depths up to 1 m. Within

tidal fresh and brackish marshes, they may befound within low elevation, well-drained marshes,or within high elevation, poorly-drained marshes.

Both species often form expansive, near-monospecific stands.

The two species are often found togetherthroughout British Columbia. A common

community associate within fresh marshes of lakemargins is broadleaved cattail. Within low

elevation tidal fresh marshes, common communityassociates include creeping spike rush and Lyngby’s

sedge. Within low elevation brackish marshes,common community associates include Lyngby’s

sedge, American threesquare, saltmarsh bulrush andseaside arrowgrass. Within high elevation tidal fresh

marshes, where drainage is poor, commoncommunity associates include broadleaved cattail,

small-fruited bulrush and jointed rush.

S. validus

inflorescencegeneral habit ofboth species

spikelet

achenes withbristles

scale

S. validus


Scirpus americanusSCIENTIFIC NAME

American ThreesquareCOMMON NAME

The stems of American threesquare emerge singlyor in small clusters from long, stout rhizomes. Thestems are triangular with flat to slightly concave orconvex sides. Stem height ranges between 15 and150 cm. Several leaves that start at or near thestem base range from 2 to 4 mm in width and 20to 100 cm in length.

One (1) to 6 floral spikelets, 7 to 20 mm in length,occur in a sessile compact cluster. The cluster issubtended by a prominent bract, 3 to 10 cm inlength, which appears to be a continuation of thestem. The achene is dark brown and lens shapedwith a prominent tip; it is 2 to 3 mm long andsurrounded by 2 to 6 bristles equal to or shorterthan the achene in length. The scales are brownto blackish purple, with a firm midrib extended asa short awn from the cleft tip.

American threesquare often occurs as expansive,near-monospecific stands within tidal brackishmarshes. It also occurs as scattered individuals orsmall patches within tidal fresh and salt marshes.It typically occupies the low to middle elevationsof tidal marshes. American threesquare occurswithin non-tidal fresh marshes along the shallowmargins of lakes. It occurs in British Columbiagenerally south of latitude 53° N.

Common community associates within tidalbrackish marshes are Lyngby’s sedge, Balticrush, saltmarsh bulrush, softstem bulrush,hardstem bulrush and seaside arrowgrass.

American threesquare is an important componentof delta front marshes of the Fraser River estuary.The rhizomes are extensively grazed by residentand migrating geese.

habit

spikeletcluster

achenewith bristles


general habit spikelet

habit ofinflorescence

achene withflexuous bristles

Scirpus cyperinusvar. brachypodus

SCIENTIFIC NAME

Woolly BulrushCOMMON NAME

The stems of woolly bulrush, 80 to 150 cm inheight, are grouped together as a distinctive tuft.Unlike many other Scirpus species, it does not

possess rhizomes. The leaves are flat, grass-like(not channelized as in many Carex species), up to

6 mm in width, and distributed along the entirelength of the stem.

The spikelets are small (3 to 8 mm in length) andnumerous, being borne on short, slender

peduncles within a terminal inflorescence.Numerous bracts, up to 10 cm in length, subtendthe inflorescence. Scales, approximately 1.5 mm

in length, are pale green to greenish-black withdistinctive fine, red-brown longitudinal lines.

Achenes, typically less than 1 mm in length, aretrigonous. Six (6) bristles, longer than both

achenes and scales, emerge from the base ofeach achene; these tawny, flexuous bristles give

the spikelets their woolly appearance.

Woolly bulrush occurs at mid to high elevationswithin tidal fresh marshes. Its tufted habit prevents

it from establishing near-monospecific stands;other species inhabit the spaces between

individual tufts. Woolly bulrush is often a dominantspecies within wet meadows where saturated soilspersist. It is a conspicuous component of marshes

along the margins of streams, rivers and lakes.

Common community associates include small-fruited bulrush, soft rush, reed

canary grass, creepingbentgrass, beaked sedge

and slough sedge.


Scirpus maritimusvar. paludosusSCIENTIFIC NAME

Saltmarsh BulrushCOMMON NAME

The triangular stems of saltmarsh bulrush achieveheights of 20 to 150 cm. The leaves are up to 1 cm inwidth and are well distributed along the entire lengthof the stem. The stout rhizomes often bear well-defined tubers.

The floral spikelets typically occur in a sessile,compact, terminal cluster. Subsidiary clusters ofspikelets (5 to 10) sometimes occur on shortpeduncles (to 5 cm long) emerging from the basalcluster. Spikelets are 1.2 to 2 cm in length and 1cm in width, and number from 3 to 20 per cluster.Several bracts of up to 10 cm in length extend fromthe base of the spikelets. The lenticular achenes areapproximately 3 mm in length and surrounded by 2 to6 barbed bristles up to 1.5 mm in length. The scalesare tan to dark brown with a midvein extended intoa short awn that emerges from a notch at the endof each scale.

Saltmarsh bulrush occurs within tidal brackishmarshes, often as expansive near-monospecificstands. It typically occupies the low to mid elevationsof these marshes. Common community associatesinclude Lyngby’s sedge, Americanthreesquare, softstem bulrush, hardstembulrush and seaside arrowgrass. Saltmarshbulrush also occurs within inland fresh andalkali marshes. It occurs within BritishColumbia generally south of latitude 53° N.

Despite its name, saltmarsh bulrush doesnot typically inhabit tidal salt marshes ofBritish Columbia. These marshes areinhabited by more classic halophytessuch as pickleweed and saltgrass.

As for American threesquare,saltmarsh bulrush is an importantcomponent of delta front marshesof the Fraser River estuary. Thetubers and rhizomes are extensivelygrazed by resident and migratinggeese.

achene withbristles

spikelet

habit

spikeletclusters


habit

spikelet

scale

Scirpus microcarpusSCIENTIFIC NAME

Small-fruited BulrushCOMMON NAME

Distinctly triangular stems, 60 to 150 cm in height,arise from long, stout rhizomes. The channelized

leaves are 1 to 2 cm in width and are borne by thestem throughout its length.

The inflorescence consists of several spreadingstalks terminally adorned with clusters of small

spikelets. Distinctive bracts occur at the base of theinflorescence. The lenticular achenes, approximately

1 mm in length, characterized by a distinctive stylarapiculus, are adorned by 4 to 6 bristles that slightly

surpass the length of the achene. The scales areapproximately 1.5 mm in length, greenish-black with

a pale green mid-rib.

Small-fruited bulrush occurs within fresh wetlands. Itoccurs sporadically or as relatively small

monospecific patches within the high elevation zoneof tidal fresh marshes. It occurs within the understory

of open canopy tidal and riparian (floodplain)swamps. Small-fruited bulrush occurs within wet

meadows and along the margins of shallow ponds. Itprospers within saturated soils, but does not appear

to withstand either extended or frequent (e.g.inundated twice daily by tides) periods of inundation.

Common community associates within tidal freshmarshes include broadleaved cattail, softstem

bulrush, hardstem bulrush and jointed rush. Withinfresh swamps, it is often found with slough sedge.

Common community associates within wetmeadows include reed canary grass, woolly

bulrush, beaked sedge, soft rush andcreeping bentgrass.

achene withbristles


tall habit

Eleocharis palustrisSCIENTIFIC NAME

Creeping Spike RushCOMMON NAME

The slender to stout stems of creeping spike rushachieve heights of 10 to 100 cm; they are round tooval in cross section. The stems emergeindividually or in small clusters along creepingrhizomes. The leaves are reduced, occurring assheaths at the base of the stem.

A solitary floral spikelet 5 to 23 mm in lengthoccurs at the top of the stem. The achenes arelens shaped, 1 to 1.5 mm in length, and areadorned with a terminal conical tubercle. Four (4)bristles surround and exceed the achene inlength.

Creeping spike rush is a conspicuous componentof low elevation tidal fresh and low salinitybrackish marshes, where it often occurs as anarrow, linear, near-monospecific stand. It is alsocommon throughout British Columbia within avariety of inland fresh wetlands.

Within tidal marshes, common communityassociates include softstem bulrush, hardstembulrush, Lyngby’s sedge and jointed rush.

robust spikemorphology

slender spikemorphology

achene withtubercle andbristles

short habit


Juncus articulatusSCIENTIFIC NAME

Jointed RushCOMMON NAME

The stems of jointed rush are 15 to 30 cm inlength. Larger plants are conspicuously tufted,

with stems emerging from short rhizomes or thelower nodes (adventitiously) of a primary stem.

The leaves occur throughout the entire length ofthe stem; they possess complete septa and

rounded conspicuous auricles.

Numerous floral heads, consisting of 6 to 12flowers, on mostly spreading branches, comprisethe terminal inflorescence. The involucral bract is

shorter than the 2 to 15 cm long inflorescence.The petals and sepals of each flower appear

superficially to be scales. They are typically brownand 2.5 to 3 mm in length. The dry fruit or capsuleis conic-ovoid, rather uniformly tapered to the top,and somewhat triangular with distinct ridges. The

capsule is longer than the perianth. The seeds areup to 0.5 mm in length, ellipsoid, sharply tipped,

and lightly striated longitudinally.

Jointed rush appears within mid to low elevationsof tidal fresh marshes, where it often forms

isolated monospecific patches. It functions as apioneer species within recently disturbed mid tolow elevation tidal fresh marshes; it will colonize

and dominate the disturbed area for severalseasons before being displaced by species

typically dominant at that elevation. It occurssporadically within poorly drained high elevationportions of tidal fresh marshes. It is often found

within tidal brackish marshes where fresh seepsor discharges occur (e.g. stormwater outfalls). It

occurs sporadically along the margins of streamsand lakes. Jointed rush occurs throughout coastal

and southern inland portions of British Columbia.

Common community associates within low to midelevation tidal fresh marshes include Lyngby’s

sedge and creeping spike rush. Within high elevationtidal fresh marshes, where drainage is poor,

common community associates include softstembulrush, hardstem bulrush, broadleaved cattail and

small-fruited bulrush.

seed

base of stemdisplaying auricle

capsule withperianth

habit


Juncus balticusSCIENTIFIC NAME

Baltic RushCOMMON NAME

The cylindrical stems of Baltic rush emerge fromstout, spreading rhizomes. The stems are 15 to80 cm in height and 1.5 to 4 mm wide at the base.If present, the leaves are reduced, occurring assheaths at the base of the stem.

The inflorescence is borne laterally off the stem; itis subtended by a prominent bract 5 to 20 cm inlength that appears to be a continuation of thestem. The petals and sepals of each flower,collectively known as the perianth, appearsuperficially to be scales. They are 4 to 5 mm inlength and green to brown in colour with a greenmidstreak. The dry fruit, a capsule, is ovoid andshorter in length than the perianth. Seeds areapproximately 0.6 mm in length, ovoid-ellipsoid,finely reticulate, with minute tips.

Baltic rush often occurs as near-monospecificstands at mid to high elevations within tidalbrackish and fresh marshes. It prefers well-draining substrates, with stands often formingdiscernable hummocks. Inland, Baltic rush maybe found along the margins of lakes and withinbogs.

Lyngby’s sedge is a common communityassociate within tidal fresh marshes. Lyngby’ssedge and American threesquare are commoncommunity associates within tidal brackishmarshes.

inflorescence

seeds with and withoutmembranous coat

perianthencompassingcapsules

habit


habit

compactinflorescence

looseinflorescence

seed

capsule withperianth

Juncus effususSCIENTIFIC NAME

Soft RushCOMMON NAME

This strongly tufted plant is characterized bycylindrical hollow stems and stout rhizomes. The

stems are 20 to 100 cm in height and 1.5 to 3 mmin diameter. Leaves are reduced, occurring as

brown sheaths at the base of each stem.

The inflorescence is borne laterally off the stem; itis subtended by a prominent bract, 5 to 20 cmlong, which appears to be a continuation of the

stem. The petals and sepals of each flower,collectively known as the perianth, appear

superficially to be scales. They are green to brown incolour, and 2.5 to 3.5 mm in length. The dry fruit,

known as a capsule, is slightly shorter or equal inlength to the perianth. The capsule is obovate,

slightly triangular with distinct ridges and blunt nearthe top. Seeds are approximately 0.4 mm in length,

ellipsoid, finely ridged, with minute tips.

Soft rush is a highly variable plant, displayingnumerous distinct inflorescence morphologies. Ninevarieties have been identified within North America,

four of which are known in the Pacific Northwest.

Soft rush may be found almost wherever saturatedsoils persist. It does not appear to withstand

either long or frequent (e.g. inundated twice dailyby tides) periods of inundation. Soft rush is

restricted to fresh marshes. Within tidal freshmarshes, it is found sporadically at highelevations. Despite its tufted habitat, its

rhizomatous nature allows it to establish near-monospecific stands within wet meadows and

shallow fresh marshes. Soft rush has beenidentified as an agricultural pest within cultivated

wet fields. It is common within roadside ditches,drainage swales and recently disturbed wet sites. It

is found throughout British Columbia.

Common community associateswithin wet meadows and shallow fresh

marshes include bentgrass, woollybulrush, reed canary grass, small-fruited

bulrush and beaked sedge.


habit

blade, sheathand ligule

glumes

A. stolonifera

A. stolonifera

Agrostis stoloniferaA. exarataSCIENTIFIC NAMES

Creeping BentgrassSpike BentgrassCOMMON NAMES

Creeping bentgrass has both stolons andrhizomes. It may display either an erect orprostrate and stoloniferous habit. The stems are50 to 120 cm in height. The ligules are truncate toobtuse, with those of the upper stem leaves 3 to 6mm in length. The leaves may be flat or folded and2 to 10 mm in length.

Spike bentgrass typically displays a tufted habit,with the erect stems closely gathered together.The stems sometime bend and root from basalnodes. The stems achieve heights of 20 to 120cm. Short rhizomes often extend outwards fromthe tuft. The ligules are similar in morphology tothose of creeping bentgrass, ranging in lengthfrom 3 to 8 mm. The leaves are flat and typicallyscabrous.


A. exarata

glumes

The inflorescence is similar for both species. It is 5to 30 cm in length, narrow and spike-like tosomewhat open, and purplish in colour. The

branches of the inflorescence in creeping bentgrassare appressed to ascending, while the branches inspike bentgrass are always strongly ascending to

erect. The branches of both species bear spikeletsalmost to the base. The glumes are small (2.5 to 3mm in A. stolonifera; 2.5 to 4.5 mm in A. exarata).

The lemmas in both species are shorter than theglumes, ranging in length from 1.5 to 2.5 mm.Creeping bentgrass is typically awnless, while

spike bentgrass may be awned or awnless. Theawns, if present, are up to 5 mm in length.

Creeping bentgrass is a non-native (Europeanorigin) species that has become extensively

naturalized within southwestern British Columbia.It is commonly utilized for pastures and lawns.

Spike bentgrass is a native species. Both speciesinhabit the upper elevations of tidal brackish (low

salinity) and fresh marshes.

There are several other bentgrass speciesthat may be found within tidal fresh andbrackish marshes, specifically colonial

bentgrass (A. capillaris), redtop (A. gigantea),Oregon bentgrass (A. oregonensis) and

rough bentgrass (A. scabra).

habit

blade, sheathand ligule


Glyceria elataG. grandisSCIENTIFIC NAMES

Tall MannagrassReed MannagrassCOMMON NAMES

Both mannagrass species are stronglyrhizomatous plants, with stems emerging singlyfrom a rhizome in tall mannagrass, and multiplestems emerging from a rhizome in reedmannagrass. Tall mannagrass grows to heights of100 to 150 cm, while reed mannagrass reaches90 to 160 cm in height.

The leaves of both species are flat, with bladewidths typically 6 to 10 mm and 6 to 15 mm inwidth for tall and reed mannagrass, respectively. Intall mannagrass, the sheaths are closed near thetop and rough to the touch when rubbed towardsthe stem. In reed mannagrass, the sheaths aresmooth and closed completely or open to 1 cm.The ligules are hairy, obtuse, and are typically 3 to6 mm in length for tall mannagrass. For reedmannagrass, the ligules are 4 to 9 mm length,smooth and display a pointed tip.

The inflorescence of tall mannagrass is loose,open and spreading. It ranges in length from 15 to25 cm. The spikelets are ovate and 4 to 8flowered. The glumes are of unequal length, thefirst approximately 1 mm and the secondapproximately 0.5 mm. They are irregularlymargined (appearing torn), often with small hairs.The lemmas are 2 mm in length, 7 nerved andappearing slightly torn. The paleas are minutely cleftat the tip.

glumes

habit

G. elata

G. elata


glumeshabit

G. grandis

The inflorescence of reed mannagrass is loose,open and spreading with numerous branches. It

ranges in length from 20 to 35 cm. The spikeletsare somewhat loose, slightly flattened, oblong and4 to 7 flowered. The glumes are of unequal length,

the first approximately 1.5 to 2 mm and thesecond approximately 0.7 to 1 mm. They are

irregularly margined, often with small hairs. Thelemmas are 2 to 3 mm in length, 7 nerved,

purplish and slightly torn looking at the blunt tip.The paleas are abruptly notched and sometimes

appear torn at the tip.

Both grasses may be observed within shallownon-tidal fresh marshes and wet meadows, and

high elevation tidal fresh and low salinitybrackish tidal marshes.


inflorescence

blade, liguleand sheath

base of stem displayingrhizomes and rootsglumeslemma

Phalaris arundinaceaSCIENTIFIC NAME

Reed Canary GrassCOMMON NAME

This strongly rhizomatous grass grows to heightsof 70 to 140 cm. The stem is hollow and up to 1cm in diameter. The leaves are flat, 7 to 20 mm inwidth and up to 30 cm in length. Ligules are 4 to10 mm in length, obtuse, lacerate and turnedbackwards.

The inflorescence is typically 8 to 15 cm in length,compact, with the branches spreading only atanthesis. The spikelets consist of groups of 3flowers. The glumes are slightly unequal in length(4.5 to 5 mm), 3 nerved and minutely hairy. Thefertile lemma is 3 to 4.5 mm in length and nearsmooth with 5 inconspicuous nerves. The palea isshorter than the lemma.

Reed canary grass inhabits a wide range of freshwetland types. It thrives where saturated soilconditions persist without extended periods ofstanding water. It is also capable of establishingvigorous stands within seasonally floodedenvironments. Its ability to tolerate a wide rangeof inundation regimes within non-tidal freshwetlands confers it a competitive advantage overother plant species, allowing it to persist asnear-monospecific stands.

Reed canary grass often inhabits the highestelevations of tidal fresh marshes. It is a dominantplant of the banks of agricultural sloughs, highwayditches, dikes and other linear public works right-of-ways characterized by wet soils and frequentdisturbance (e.g. mowing). It is also a dominantspecies within wet meadows.


Calamagrostiscanadensis

SCIENTIFIC NAME

Bluejoint ReedgrassCOMMON NAME

This strongly rhizomatous grass grows to 1.2 m inheight. The stems are smooth. The ligules are

delicately membranous, 3 to 8 mm in length, andstrongly lacerate on all but the basal leaves. The

leaves are typically flat and 3 to 8 mm in width.

The inflorescence is usually open, nodding and 10to 25 cm in length. It is sometimes very narrow,

approximately 1.5 cm across at maturity. Theglumes are purplish in colour when mature, and

range in length from 2.5 to 6 mm. They areslenderly to gradually acuminate to abruptly acuteand usually scabrous, always so on the keel. The

lemmas are shorter than the glumes, membranousand papery, and plainly to obscurely nerved above.

The straight, slender awns are attached frombelow the midlength to the top of the lemma.

Numerous callus hairs adorn the spikelet; they areat least 3/4 the length of the lemma.

Bluejoint reedgrass inhabits a variety of wetlands.It occurs sporadically within tidal fresh marshes. Itestablishes near-monospecific stands within non-

tidal wetlands such as wet meadows, marshesand fens. It is a common inhabitant of the fringes

of streams, rivers and lakes. Common communityassociates include water sedge, beaked sedge,

slough sedge and hardhack. Within fens, it is oftenfound together with Pacific crabapple and willows.

lemma

habit

glumes


femaleglumes

maleglumes

habitblade, sheath and ligule

Distichlis spicataSCIENTIFIC NAME

SaltgrassCOMMON NAME

This rhizomatous grass grows up to 40 cm inheight. In contrast to many other grasses, itsstems are solid. The leaves are bilaterallysymmetrical, stiff, sharp-pointed and 2 to 4 mm inwidth. Auricles are not present on the leaves; theligule is short (to 0.5 mm in length) and fringedwith hairs.

Male and female flowers occur on separate plants;the inflorescence is small and compact. Thepedicels of the spikelets are typically not evident,with the male and female glumes 2 to 2.5 mm and3 to 3.5 mm in length, respectively. The lemmasare unawned, hardened, 4.5 to 6 mm in length,with 9 to 11 convergent obscure nerves.

Saltgrass inhabits low to high elevations withinsalt marshes. It regulates its internal salt contentby excreting salt via special cells in its leaves.This ability to regulate salt allows it to inhabithypersaline soils, such as those that characterizesalt pans within high elevation salt marshes.

Saltgrass often occurs as a dense monospecificstand, especially at high elevations. A commoncommunity associate within mixed communitiesis pickleweed.

A closely related species, Distichlis stricta,inhabits the margins of alkaline ponds, alkalineflats, and sandy lake shores within inlandenvironments.


inflorescence

Salicornia virginicaS. europaea

SCIENTIFIC NAMES

Perennial PickleweedAnnual Pickleweed

COMMON NAMES

Salicornia virginica is a perennial pickleweedthat possesses distinctive, jointed, fleshy stems

up to 1 m in length. The stems may beprostrate, ascending or erect in habit. The leaves

are extremely reduced, occurring as smallscales. New growth is succulent and may take

on a reddish tinge. In winter, most of thesucculent growth is lost, leaving only the woody

perennial stems.

Numerous erect flowering stems, approximately 5to 30 cm in length, are distinguished by theirbrown purplish colour and the 1 to 4 cm longflowering spikes. The tiny yellow flowers are

clustered at the tips of the stems, emerging fromdepressions at the joints.

Pickleweed is the most common plant within lowelevation salt marshes. It often forms dense,

monospecific mats up to 20 cm thick.

A community associate is often an annualspecies of pickleweed, S. europaea (S.

herbacea). This annual pickleweed does notpossess rhizomes or woody stems. It is

characterized by an erect stem habit. S. rubra isan inland species that inhabits moist saline andalkaline soils. Like S. europaea, S. rubra is an

annual species.

Other common community associates of perennialpickleweed include saltgrass and arrowgrass.

inflorescence

habit

S. virginica

habit

S. europaea

S. virginica


basalsheath

habit

basal tuft

fruitflower

Triglochin maritimumSCIENTIFIC NAME

Seaside ArrowgrassCOMMON NAME

Fleshy, succulent leaves, 10 to 80 cm in length,occur as tufts emerging from short, stoutrhizomes. The blades are somewhat flattened andare 1.5 to 2.5 cm in width. Each leaf ischaracterized by a basal sheath that encircles upto as much as one-third of the lower portion of animmediately preceding older leaf.

The flowering stem, 30 to 120 cm in length,emerges from the centre of the tuft. Tiny greenflowers, with distinctive feathery red to purplestamens, occur on individual stalks along theupper third of the stem. The dry fruits are elliptic-ovate (egg-shaped), approximately 5 mm inlength, and are composed of six one-seededcompartments that split lengthwise along thecentral axis of the fruit.

Seaside arrowgrass often forms dense stands inlow elevation tidal salt and brackish marshes thatare inundated twice daily. Unlike standsdominated by sedges and bulrushes, coveragewithin these stands is often incomplete, withexposed substrates occurring between the tufts ofindividual plants. It occurs sporadically within highelevation tidal marshes that are typicallyinundated only once per day. It occurs throughoutcoastal British Columbia.

Seaside arrowgrass occurs sporadically withinstands of saltgrass and pickleweed. It may befound with Lyngby’s sedge, Americanthreesquare, softstem bulrush, hardstem bulrushand saltmarsh bulrush in brackish marshes.


Typha latifoliaSCIENTIFIC NAME

Broadleaved CattailCOMMON NAME

The cylindrical, pithy stems of broadleaved cattailgrow to 3 m in height. The alternating leaves aresheathing, strap-like, convex, and 8 to 20 mm in

width. The stems emerge from large, stout rhizomes.

The tiny flowers are crowded within terminal,cylindrical spike-like inflorescences that are

divided into distinct male and female segments.These segments are typically continuous, withthe male segment occurring above the female.

When flowering, there is a stark contrast betweenmale and female segments, with the male brightyellow (with pollen), and the female bright green.When in fruit, the female segment consists of a

dark brown cylinder 15 to 20 cm in length and 12to 30 mm in width. The fruits consist of 1 mm

long nutlets, ellipsoid in shape, with numeroushairs emerging from the base.

Broadleaved cattail is a very common speciesthat occurs throughout British Columbia where

saturated soil conditions persist. It often occursas expansive monospecific stands. It is

intolerant of salt water, and as a result, isrestricted to very low salinity brackish and fresh

wetlands. Within tidal fresh marshes it occurs athigh elevations. In relatively well draining

marshes, common community associatesinclude reed canary grass, Lyngby’s sedge and

beaked sedge. In relatively poor drainingmarshes, common community associates

include softstem bulrush, hardstem bulrush,small-fruited bulrush and jointed rush. Along the

margins of lakes and within shallow fresh ponds,common community associates includesoftstem bulrush and hardstem bulrush.

habit

fruits

spike

malesegment

femalesegment


flower

Acer circinatumSCIENTIFIC NAME

Vine MapleCOMMON NAME

Vine maple occurs as a shrub or small tree to 10 min height, with a trunk diameter to 15 cm. Its habitvaries from an upright single trunk with severalbranches to a sprawling assemblage of crooked,prostrate trunks. The bark is light green when young,becoming increasingly brown and marked with age.

The leaves are opposite, 3 to 12 cm across with 7 to9 radiating lobes. The leaves are hairy uponemergence in spring, becoming hairless later duringthe growing season. The margins are single ordouble toothed. In autumn, leaves within shadedenvironments typically turn yellow, while leaves withinexposed environments typically turn bright red.

The flowers range from 6 to 12 mm across, and arecharacterized by 5 red to purple sepals and 5 whitepetals. The flowers are borne in loose droopingclusters at the end of shoots. The flowers transforminto winged fruits progressively from the top of thecluster to the bottom. Winged fruits are borne inpairs, each 2 to 4 cm in length. The fruits areoriented approximately 180° to each other. The fruitsare initially green, turning bright red in late summer.

Vine maple occurs within a variety of woodlandcommunities. It occurs within the understory of opencanopy mixed woodlands, along the margins ofdense canopy woodlands, and along the margins ofstreams and rivers within high elevation floodplainenvironments. It inhabits moist to wet sites; it isintolerant of flooding.

Common community associates include snowberry,Indian plum, thimbleberry and salmonberry.

leaf and fruits


flowerfruits

leaf and inflorescence

Acer macrophyllumSCIENTIFIC NAME

Broadleaf MapleCOMMON NAME

Broadleaf maple is a medium sized tree, growingup to 35 m in height and 100 cm in diameter. Its

habit varies from a branch-free trunk with a narrowcrown (within a dense stand of trees), to several

large spreading and ascending limbs with a broad,rounded crown (within open woodlands). In young

individuals, the bark is grayish-brown and smooth,while in older individuals, the bark displays narrow,

scaly ridges.

The leaves are opposite with 5 deeply notchedlobes. Leaves are typically 15 to 30 cm in width;they may be up to 60 cm across. In older trees,

the leaves are dark green above and lighter below.In younger trees, the leaves appear somewhat

lighter, almost chlorotic. The leaves turn yellowin autumn.

The flowers are approximately 10 mm across,greenish yellow, and occur within hanging

drooping clusters. Male and female flowers occurtogether. They typically emerge prior to the leaves.

The winged fruits emerge in pairs, in a ‘v’configuration, and are each approximately 3

to 6 cm long. The swollen seedcase iscovered with small, needle-like hairs.

Broadleaf maple typically occurs on coarse,gravelly, moist soils in pure or mixed stands.

Common understory and edge speciesinclude vine maple, Saskatoon,beaked hazelnut, thimbleberry,salmonberry, Indian plum, red

elderberry and snowberry.


nutlet

flowering female (short)and male (long) catkins

leaves and maturefemale catkins

Alnus rubraSCIENTIFIC NAME

Red AlderCOMMON NAME

Red alder is a medium sized tree that grows up to25 m in height and 80 cm in diameter. The bark issmooth, thin and light gray in colour. The bark ofolder trees is lightly furrowed. New shoots areangular and lobbing.

The leaves are oval to rhombic, 5 to 15 cm long,and tapered from the middle to both ends. Leavesare dull green above and range in colour belowfrom grey-green (young leaves) to rusty brown(old leaves). The margin is double-toothed androlled under. There is considerable leaf fall duringthe summer; the leaves remain green above untilthey fall.

The flowers are borne on catkins. The catkinsflower before the leaves have enlarged, developingon the growth of the previous season. Floweringmale catkins are 10 to 15 cm in length. Floweringfemale catkins are up to 5 mm in length.

Mature female catkins are woody, ovoid-ellipsoidstructures, 1.5 to 2 cm in length and 1 cm inwidth. The nutlets are about 2 mm in length,narrow winged or encircled by a wing. The nutletsripen in late autumn and are shed throughout lateautumn and winter.

Red alder is restricted to the coast, where it isoften the most common broadleaved tree. It isone of the first colonizers of cleared lands,often establishing near monospecific stands.It is often a dominant tree of tidal swampsthat are inundated no more than onceduring each tide cycle.


Betula papyriferaSCIENTIFIC NAME

Paper BirchCOMMON NAME

Paper birch occurs as a short tree, to 20 m inheight with tight reddish bark, or a tall tree, to 35

m in height with orange-white bark. In general, thebark is thin, dark red to almost black on young

stems, becoming reddish-brown and then creamywhite, often shredding in large sheets. Dark

lenticels adorn the bark throughout.

The leaves are 5 to 10 cm long, oval to triangularwith the tip pointed. The base of the leaf is broadlywedge shaped, rounded, straight, or cordate. The

leaf margin is double-toothed (i.e. two teethbetween veins). The leaves are dull green above

and lighter below.

The male and female flowers occur on separatecatkins. Immature male catkins occur in clustersof 1 to 3, are 1 to 3 cm long and 2 to 4 mm wide;pollen releasing catkins are approximately 9 cm

long. Immature female catkins are 1 to 2 cm long,erect, with pink or red stigmas; mature female

(seed) catkins are 3 to 5 cm long.

Nutlets are 1.5 to 2.5 mm long, and about half aswide; the wings are much wider than the nutlet.

Attached scales are variable, approximately 2 to 3mm in length, usually hairy, with 2 rounded laterallobes diverging from a short pointed central lobe.

Fruits and scales are shed fromSeptember onwards.

Paper birch typically grows in moist openwoodlands. It often occurs within and along

the margins of fens and bogs. Commonunderstory and edge species include black

twinberry, red osier dogwood, beakedhazelnut, Nootka rose, hardhack,thimbleberry and salmonberry. A

common cohort within fens and bogsis shore pine.

nutlets

flowering female(short) and male(long) catkins

leavesand fruitcatkins


fruit

Cornus stoloniferaSCIENTIFIC NAME

Red Osier DogwoodCOMMON NAME

Red osier dogwood occurs as a small to largeshrub 1 to 6 m in height. It is freely branched, andoften exhibits a prostrate habit. The branches areopposite. During the growing season, the bark ofyoung stems is light to dark green, with older barkoften displaying patches of grey callus. Upon theonset of fall, the bark, especially that of youngstems, turns bright red.

The leaves are opposite. The leaf buds are narrowand pointed, and in contrast to willows, are naked.The leaves are dark green above, and lighter andhairy below. The leaves are oval, 10 to 20 cm inlength, smooth edged, with approximately 5-7prominent veins that converge to a sharp point atthe distal end of the leaf. The leaves turn a deepred in autumn.

The flowers are characterized by 4 small petals, 2to 4 mm in length, white to green in colour. Theflowers are organized in dense, flat toppedterminal clusters.

The fruits consist of small, roundish drupes 6 to 9mm in length. The drupes are white to faded bluein colour.

On the coast, red osier dogwood often flowerstwice during the growing season. The firstflowering occurs on the stems of the previousgrowing season during middle to late spring. Thesecond flowering occurs on the stems of thecurrent growing season during middle to latesummer. The second flowers often occur on theplant together with the first berries.

Red osier dogwood grows along the margins andthe floodplains of streams and rivers. It occurswithin non-tidal and tidal swamps. Within openbroadleaved forests, common communityassociates include black twinberry, salmonberry,Pacific ninebark, willows and cascara. Commoncommunity associates within fresh swampsinclude small-fruited bulrush, slough sedge,broadleaved cattail, hardhack, black twinberry andwillows.

leaves

flower


Corylus cornutaSCIENTIFIC NAME

Beaked HazelnutCOMMON NAME

Beaked hazelenut is a large shrub, growing up to6 m in height. Larger shrubs are characterized by

densely clumped, spreading stems. Newlyelongated shoots and leaves are covered in

conspicuous soft, white hairs. The bark of youngshoots and stems is greenish-brown to reddish-

brown, with numerous, small lenticels. Thelenticels on older bark are obscured by

longitudinal fissures.

The alternate leaves are elliptic to ovate, beingsomewhat heart-shaped with a pointed tip. The

margins of the leaves are doubly saw-toothed. Theleaves are light green, paler below than above.

Older plants display a conspicuous die-back ofolder leaves during mid-summer. The leaves turn a

necrotic yellow in autumn.

The male flowers occur within slender catkins nearthe tips of shoots of the previous year. The female

flowers are small and are enclosed within abractlet. The purplish red styles of the female

flowers barely extend beyond the bractlets. Thecatkins and bractlets appear during early autumn,

overwintering prior to flowering.

The spherical, edible nuts are enclosed in tubularhusks that are constricted beyond the apex of thenut into a beak. The husks are light green, sticky,

and covered with stiff prickly hairs. The fruits occurin groups of 1 to 3.

Beaked hazelnut is characteristic of openbroadleaved forests of southern British Columbia.

It occurs within moist but well-drained sites at lowto middle elevations. It occurs along streams and

rivers in predominantly coarse, well-drainedsubstrates.

Common community associates includesnowberry, thimbleberry, red elderberry and

Saskatoon.

flowering female (redand short) and male(yellow and long) catkins

twinned fruits and leaves

single fruit


Crataegus douglasiiSCIENTIFIC NAME

Black HawthornCOMMON NAME

Black hawthorn grows to 11 m in height. Itdisplays both shrub and tree habits. The tree habitis often characterized by a crooked trunk(s). Theshrub habit is multi-stemmed and scraggly inappearance. The bark is greyish brown withshredding scales. The branches are armed withthorns to 3 cm in length.

The alternate leaves are 2 to 8 cm in length,coarsely double-toothed with 5 to 9 lobes from themiddle of the leaf to the distal end. The leaves aresomewhat leathery with few hairs if present.

The white flowers are approximately 1 cm acrossand display 5 petals. They are borne in clustersterminally or at the leaf axil.

The fruits appear as little apples; they are ovoid, 8 to10 cm across and dark reddish-purple in colourwhen ripe.

Along with other hawthorn species, blackhawthorn is common along the fence rows ofagricultural fields. It may be found within openbroadleaved forests along the margins of streamsand rivers. It occurs at the higher elevations of non-tidal and tidal fresh swamps. Common communityassociates include hardhack, Nootka rose, blacktwinberry, Pacific ninebark, red osier dogwood,willows and Pacific crabapple.

Another common species of hawthorn is thenaturalized English hawthorn (C. monogyna). Itcan be distinguished from black hawthorn by itsdeeply lobed leaves and by thorns that bearleaves.

fruit

C. monogyna

C. douglasii

leaves, fruitsand thorns

flower


berriesand bracts

flowers

berriesand leaves

flowersand leaves

Lonicera involucrataSCIENTIFIC NAME

Black TwinberryCOMMON NAME

Black twinberry is a medium sized shrub thatgrows up to 3 m in height. It typically occurs as a

scraggly assemblage of stems, rarely assumingthe habit of an erect shrub. Young shoots (thosethat emerge during the current growing season)

are light green and somewhat square torectangular in cross-section.

The leaves are elliptical to broadly lance-shaped, 5to 14 cm in length and 2 to 8 cm in width. They

are medium to light green, and turn yellow toorange to red in autumn. They are glabrous above

and pubescent below.

The yellow flowers are tubular with five lobes at theopen end of the flower, each representing thedistal portion of a fused petal. They occur as

pairs, 1 to 2 cm in length, and are cupped at thebase by green to purplish bracts.

The fruits are shiny black berries cupped bypurplish to maroon bracts. The berries are

approximately 1 cm across and produce 3 seeds.

Black twinberry is a common component of openforests along the margins and floodplains of

streams and rivers. It is common within fens, andnon-tidal and tidal fresh swamps. Common

community associates include salmonberry,hardhack, red osier dogwood,

willows, Pacificninebark, Pacificcrabapple, black

hawthorn andcascara.


Osmaronia cerasiformisSCIENTIFIC NAME

Indian PlumCOMMON NAME

Indian plum grows to 5 m in height. For its heightit is not especially robust, being characterized bya myriad of loosely organized branches thattypically bear leaves distally. It does not present aconsistent habit. Young shoots (those thatemerge during the current growing season) arelight green, with older shoots purplish brown.Older plants often bear numerous dead branches.

The leaves are borne alternately along the stemand branches, with terminally borne leaves oftenpresented in a whorl. The leaves are broadly lanceshaped, 5 to 12 cm in length, with smoothmargins. In late summer, older leaves commenceto change colour from the characteristic lightgreen to yellow with some orange. Theappearance is distinctive; the plants display greenleaves off the terminal shoots and yellow andorange leaves off subordinate shoots.

The flowers of Indian plum are one of the first toemerge during early spring, emerging prior to theleaves. The flowers are greenish-white and occurwithin drooping clusters 5 to 10 cm in length. Theclusters emerge from the nodes that bear theleaves. Male and female flowers are borne onseparate plants. The calyx is partially fused, withthe 5 petals emerging from a bell-shaped base. Itis 6 to 7 mm in length, with petals 5 to 6 mmin length.

The fruits appear like small plums, displaying abluish black colour when ripe. These small drupesare 8 to 10 mm in length. The seed is large relativeto the overall size of the fruit.

Indian plum typically occurs within openbroadleaved forests. It occurs sporadically alongthe margins of streams and rivers. Commoncommunity associates include snowberry,salmonberry, thimbleberry, red elderberry, redosier dogwood and vine maple.

fruitsand leaves

flowersand leaves section of

flower

external viewof flower


Physocarpus capitatusSCIENTIFIC NAME

Pacific NinebarkCOMMON NAME

Pacific ninebark is a large shrub, attaining heightsof up to 5 m. It typically occurs in clumps, with

the major trunks and branches cascading ordrooping. The bark is brown and shreds into

thin strips.

The deciduous leaves are alternate, 3 to 6 cm inlength, with 3 to 5 toothed lobes. They are shiny

dark green above and lighter below with smallhairs. The leaves turn a necrotic yellow in autumn.

The flowers are organized within rounded clusters.Each flower consists of 5 white petals and is

approximately 8 mm across. The fruits consist ofreddish brown dried follicles approximately 1 cm in

length. The inflated follicles contain numeroussmall shiny seeds, each ranging in length from 2.3

to 2.8 mm.

Pacific ninebark occurs within moist to wet soilsof open non-tidal and tidal fresh swamps, margins

and floodplains of streams and rivers, and openbroadleaved forests. Common community

associates include red elderberry, salmonberry,thimbleberry, snowberry, hardhack, black

twinberry, red osier dogwood, willows, blackhawthorn, Pacific crabapple and cascara.

flowers and leaves

follicles


Picea sitchensisSCIENTIFIC NAME

Sitka SpruceCOMMON NAME

Sitka spruce grows to 70 m in height and 2 m indiameter. The often buttressed trunk is massive,at times reaching widths of up to 5 m. Theprincipal branches are horizontal with secondarybranches drooping. The bark is thin, reddish-brownto grey-brown, breaking into small scales withage.

The needles vary from light green to blue-green incolour, with 2 white lines of stomata above andusually 2 relatively narrower lines below. Theneedles are stiff, very sharp, 4-sided, andsomewhat flattened.

The male cones are red. The cylindrical female(seed) cones are 5 to 10 cm in length. Whenmature, the scales are yellow to light brown, thin,brittle, loose-fitting, elongated and broadest nearthe middle. The outer margin of each scale iswavy and irregularly toothed. The bracts are visiblebetween open scales. The cones open during lateautumn, and subsequently shed the reddish-brown, 2 to 3 mm long seeds that are adornedwith 5 to 8 mm long wings.

Sitka spruce is typically maritime, occurring alongthe margins of inlets and riparian corridors toapproximately 150 km inland and to 500 m inelevation. Notable exceptions are the QueenCharlotte Islands and southeast Alaska whereSitka spruce reaches the timberline. It occurs inpure or mixed stands, often on moist, well-drainedsites such as alluvial floodplains. It also occurs onold logs or mounds within bogs.

needles

needleorientation

scalewinged seed

matureseed cones


base ofneedle pair

immatureseed cone

mature seed coneand needles

matureseed cone

cluster ofpollen cones

winged seed

Pinus contortavar. contorta

SCIENTIFIC NAME

Shore PineCOMMON NAME

Shore pine is a small tree, growing up to 20 m inheight, with multiple branches and a crookedtrunk. The bark is thick, and becomes deeply

furrowed with age into thick, coarse, dark reddish-brown plates.

Needles occur in pairs and are often curved andtwisted. They range in length from 2 to 7 cm.

The yellowish-orange male (pollen) cones occur inclusters at the base of new shoots in spring. The

small female (seed) cones are scarlet red incolour, and occur at the tip of the new shoots.Subsequent to pollination, a second phase of

shoot elongation typically occurs, with the seedcone being positioned at the base of the second

shoot. Upon maturity, the egg-shaped seed conesare 3 to 6 cm in length and often slightly curved.

The scales are stiff and brown with a sharp prickleat the tip.

Shore pine inhabits a variety of habitats fromdunes and bogs to rocky escarpments, knolls and

exposed outer-coast shorelines.

Shore pine is one of two varieties of Pinuscontorta. The other, lodgepole pine (P. contorta

var. latifolia), is an inland tree that is relatively tall(to 30 m) and straight.


female flower

leaves and femalecatkins

Populus trichocarpaSCIENTIFIC NAME

Black CottonwoodCOMMON NAME

Black cottonwood is a large deciduous tree thatgrows to 60 m in height and 2 m in diameter. Thebark of older trees is deeply furrowed and darkgrey. The angular young shoots are adorned withsticky (resinous) buds, while the bark of youngshoots is smooth, grayish-green or yellowish-grey.

The leaves are broadly ovate, 5 to 15 cm in length,sometimes wedge or heart-shaped with a sharplypointed tip. The margins of the leaves are finelytoothed, the rounded teeth turning inward, somuch so that the margins appear smooth. Theleaves are dark green above and silvery greenbelow, often marked with spots of dark resin. Theleaves turn a necrotic to bright yellow in autumn.The petioles are round in cross section and 3 to 4cm in length. They bear a pair of glands at thejunction with the blade.

Flowers are borne on catkins. Male and femalecatkins, respectively, are 4 to 5 and 6 to 8 cm inlength and occur on separate plants. Maturefemale (seed) catkins are 12 to 15 cm in lengthand bear many closely spaced capsules. Thecapsules are nearly globular, 3 to 4 mm in length,covered in short hairs, and split into 3 parts whenmature. The seeds are 2 mm in length.

Black cottonwood often occurs as thedominant canopy species of floodplainforests of large rivers throughoutcoastal British Columbia. It is alsooften an important component ofmixed riparian woodlands.

Common understory and edgespecies include vine maple, redosier dogwood, willows, redelderberry, snowberry, Pacificninebark, black twinberry, thimbleberry,salmonberry and Indian plum.


flowers and leaves

fruit

Prunus emarginataSCIENTIFIC NAME

Bitter CherryCOMMON NAME

The habit of bitter cherry varies from that of ascraggly shrub to that of a tree, 2 to 20 m in

height, respectively. The trunk is slender relative tothe crown. Young bark is dark brown with

prominent orange lenticels; the lenticels of olderbark are less prominent, becoming calloused and

dark brown in colour.

The alternate leaves are dull yellowish-green,hairless to downy below. They are oblong to oval

in shape, with a finely toothed margin and roundedat the tip; this is in contrast to choke cherry (P.

virginiana) and many naturalized domesticcherries that are pointed at the tip. The 3 to 8 cmlong leaves ascend or spread stiffly from the twig.

The flowers display 5 petals that are white topinkish in colour. The flowers are 10 to 15 mm

across and occur in flat topped clusters of5 to 12 flowers.

The fruits are 1 seeded drupes that are red toalmost black in colour. They are

6 to 15 mm across.

Bitter cherry is intolerant of shade. It occurs withinopen broadleaved woodlands along the margins ofstreams and rivers. It is often a pioneer species ofrecently cleared areas. As a tree, it is typically a

minor canopy species. As a shrub, commoncommunity associates include salmonberry,

thimbleberry, red osier dogwood, hazelnut, redelderberry, willows and vine maple.


Pseudotsuga menziesiiSCIENTIFIC NAME

Douglas firCOMMON NAME

Douglas fir is a large coniferous tree that grows to70 m in height and 2 m in diameter. Young treesare characterized by pyramidal conical crownswith a stiffly erect leader. Older trees arecharacterized by long, branch-free cylindricaltrunks and short, columnar, flat-topped crowns.The principal branches occur within irregularwhorls, the upper of which often turning upright tolook like additional leaders. The larger, lowerbranches typically droop. The mature bark is verythick, deeply furrowed, rough and dark brown.

The needles are flat, 2 to 3 cm in length withpointed tips. There is one groove above with 2lines of white dots (stomata) below. The yellowish-green needles are spirally arranged along the twig,spreading out from the sides in 2 ranks orspreading out from 3 sides and moderately partedon the upper side.

The male cones are small, yellow to reddish-brown, catkin-like, 10 to 20 mm long and borne onshort stalks. The male cones are borne from theupper-middle to lower portions of the crown. Thefemale cones, at time of pollination, are oblongand approximately 30 mm in length, green topurple to red, erect on short stalks, with distinctive3-pronged bracts extending beyond the scalesand partially obscuring them. The mature seedcones are ovoid, 6 to 9 cm in length, yellowish-brown to purplish-brown on short stalks. Thescales are numerous, broad, rounded andleathery. The bracts are prominent, 3-pronged andlonger than the scales. The seeds are somewhattriangular, 5 to 7 mm in length, shiny reddishbrown, and are adorned with a wing 15 to 18 mmin length.

Douglas fir occurs on a wide variety of soils, butdoes best on deep, well-drained sandy loams withample moisture. It is commonly a pioneer speciesthat regenerates after forest fires, logging andother disturbances. It is less shade tolerant thanwestern hemlock, Sitka spruce and westernredcedar. On the coast, Douglas fir is typicallysucceeded by western hemlock, except on dry,rocky sites and areas influenced by fire.

mature seed coneand needles

scale

needleorientation

winged seed


Pyrus fuscaSCIENTIFIC NAME

Pacific CrabappleCOMMON NAME

Pacific crabapple is a shrub or small tree, rangingfrom 2 to 12 m in height. It is armed with sharp

spur-shoots. Older bark is deeply fissured.

Typically, the alternate leaves are lance to egg-shaped and up to 10 cm in length. The margins

are adorned with sharp, forward pointing teeth. Theleaves of new shoots are often characterized by

one or more prominent lobes. The leaves turnyellow to dark red in autumn.

The flowers are white to pink, have 5 petals, areapproximately 2 cm across, and occur in clustersof 5 to 12. The fruits are yellow to reddish-orange

when ripe, longer than wide and 12 to 20 mm inlength.

Pacific crabapple occurs within tidal and non-tidalfresh swamps, fens, bogs, along the margins of

coastal streams and rivers, and within moist openwoods. Within swamps, common community

associates include cascara, willows, blackhawthorn, black twinberry, red osier dogwood,Pacific ninebark, hardhack and Nootka rose.

Along the margins of streams and rivers and moistopen woods, common community associates

include salmonberry, red osier dogwood, Pacificninebark and cascara.

fruits and leaves

flowers and leaves


flowers,section andexterior view

Rhamnus purshianaSCIENTIFIC NAME

CascaraCOMMON NAME

Cascara is a large shrub to small tree that growsto 10 m in height. The bark is thin; it is smooth,dark grayish-brown in young individuals becomingincreasingly scaly with age. The dark green leavesappear waxy, are 4 to 16 cm in length, and areslightly hairy underneath. The margins of thesomewhat ovate to oblong leaves are finelytoothed. The apical leaves in young individualsoften persist through winter.

The greenish-yellow flowers occur in clusters atthe apical cluster of leaves on branches. They aresmall, 3 to 4 mm in diameter, and bear 5 sepals,petals and stamens. They typically bloom fromlate May through June.

The bluish-black to purplish-black berries areapproximately 5 to 8 mm in width. Ripe berrieswhen handled readily stain, leaving a blotchreminiscent of that left by an exploded ball-pointpen. The pits are large, 4 to 7 mm in width.

Cascara is a common inhabitant of fresh swamps,occurring within riverine floodplains and along themargins of lakes. It often occurs within mixedupland woodlands, often as a minor component ofthe canopy layer within predominantly deciduousmixed woodlands, or as a perimeter or subcanopyspecies within canopy breaks of predominantlyconiferous mixed woodlands.

As a shrub, common communityassociates include black twinberry,willows, Pacific ninebark, red osierdogwood and Pacific crabapple.

leaves and fruits


flower and leaves

hip and leaves

Rosa nutkanaSCIENTIFIC NAME

Nootka RoseCOMMON NAME

Nootka rose is a medium sized shrub that growsto 3 m in height. Large thorns adorn new shoots,

while old shoots are typically unarmed.

The alternate leaves are divided into 5 to 7 leaflets.The leaflets are 1 to 7 cm in length, elliptic in

shape and toothed along the margin.

The flowers display 5 petals that are light pink todeep rose in colour. The individual flowers are 4 to8 cm across and are typically borne terminally on

branches.

The fruits (hips) are purplish-red, round and 1 to 2cm across. They contain numerous bony hairy

achenes, 4 to 6 mm in length.

Nootka rose occurs mostfrequently along the margins and

the floodplains of streams andrivers as a component of open

shrub woodlands. It occurssporadically at the highest

elevations of tidal fresh andbrackish swamps. Common

community associatesinclude salmonberry,

thimbleberry, snowberry,hardhack, red elderberry,

willows, Pacific crabappleand black hawthorn. It and red

elderberry are often the mostprevalent shrubs, within

old field landscapes.

hips


fruit

Rubus parviflorusSCIENTIFIC NAME

ThimbleberryCOMMON NAME

Thimbleberry is a medium sized rhizomatousshrub that grows to 3 m in height. It often formsdense thickets. The bark of young green shoots(those that emerge during the current growingseason) is hairy and somewhat glandular. Thebark of older stems and branches is brown andshredding.

The leaves alternate along the stem and branches.In contrast to salmonberry leaves, thimbleberryleaves are not dissected, being maple-leaf shapedwith 3 to 7 distinct lobes. The leaves are large, upto 25 cm across. Both sides of the leaves areadorned with small hairs, rendering the leavessomewhat fuzzy.

The flowers are white with 5 petals. The petals aresomewhat crinkled in habit, much like crepepaper. The flowers occur in groups of 3 to 11 onthe end of relatively long branches.

The fruit is an aggregate of small berries,displaying a habit similar to that of the commercialraspberry. Relics of the sepals (5) areconspicuous, emerging from the base of the berryto provide a star-like backdrop. When ripe, theberries are red and adorned with small hairs thatmake the berries fuzzy. In contrast tosalmonberries, the general shape of theaggregation is semi-spherical, presentingthe appearance of a small dome.

Although thimbleberry and salmonberryoften occur together, thimbleberry, ingeneral, occurs within environments thatare drier than those inhabited bysalmonberry. It occurs along the margins andfloodplains of streams and rivers and within openwoodlands. Common community associatesinclude salmonberry, Indian plum, snowberry, redelderberry, red osier dogwood, hazelnut and bittercherry.

flowers andleaves


flowers and leaves

Rubus spectabilisSCIENTIFIC NAME

SalmonberryCOMMON NAME

Salmonberry grows to approximately 4 m in heightand is characterized by light woody stems that

break easily. The green young stems (those thatemerge during the current growing season) are

lightly armed with small thorns; these thorns falloff older stems as the golden bark shreds.

Salmonberry is characterized by branchingrhizomes that facilitate the establishment of densethickets. Both the main stem and branches have a

crooked habit, zigzagging from node to node.

The alternate leaves are typically divided into threesomewhat triangular leaflets. The leaves are dark

green and sharply toothed.

The flowers display 5 pink to purplish petals. Theflowers are 4 cm across and are borne on short

leafy branches.

The fruit is an aggregate of small berries,displaying a habit similar to that of the commercial

raspberry. The aggregation is somewhatelongated. The colour of the berries range from

orange-yellow to dark red.

Salmonberry occurs as dense thickets along themargins and floodplains of streams and rivers,

and along the margins of non-tidal and tidal freshswamps. It is a common inhabitant of moist open

forests and is common at seeps withindrier environments. It is tolerant of

widely fluctuating water tables.Common community associates

within relatively well drainingenvironments, in proximity to streams

and rivers, include Indian plum,thimbleberry, red elderberry, red osier

dogwood, Pacific ninebark, willows and vinemaple. Within swamps, common

community associates include hardhack,black twinberry, Pacific ninebark, red osierdogwood, willows, Pacific crabapple, black

hawthorn and cascara.


leaves

female catkins

Salix hookerianaS. piperiSCIENTIFIC NAMES

Hooker’s WillowPiper’s WillowCOMMON NAMES

Hooker’s willow grows to 6 m in height. The twigsare stout, dark brown and covered with gray woollyhairs for the first 2 to 3 years. The bark of olderstems is light reddish brown, shallowly furrowed,with tight scales. Lenticels that adorn the bark ofyoung stems are orange.

The alternate leaves are oval to egg-shaped. Theleaves are 4 to 12 cm in length and 2 to 6 cm inwidth, typically without a toothed margin. The tipof the leaves is rounded. Young leaves are veryhairy. The upper surface of the older leaves isnearly smooth. The stipules are small and areshed early in the growing season.

The flowers are borne on catkins, which are in turnborne on short shoots with bract-like leaves.Immature catkins are densely covered with silkyhairs. The catkins are fully developed prior to theemergence of leaves. Female catkins achievelengths of up to 12 cm, while male catkins achievelengths of up to 4 cm.

The fruits consist of dry, dehiscent capsules thatare fleshy upon initial development. They arecylindrical, 8 mm in length, beaked and smooth tosomewhat hairy.

S. hookeriana

capsule

S. hookeriana

male catkins


Piper’s willow is very similar to Hooker’s willow.The shoots and leaves are not as hairy as those ofHooker’s willow. Upon elongation, the new shoots

are finely haired; the hairs are quickly shed.Similarly, the leaves are finely haired upon

emergence and soon become smooth. The leavesare typically at least 4 times as long as wide, with

rounded to pointed teeth along the margin. Themost conspicuous distinction between Piper’s andHooker’s willow is the presence of well developed,

leaf-like stipules on Piper’s willow. Both willowsreadily hybridize.

These two willows grow in wet environments, fromopen shrub swamps to the margins and

floodplains of streams and rivers within openbroadleaved forests. Common community

associates include red osier dogwood, hardhack,salmonberry, black twinberry, other willows,

Pacific ninebark, Pacific crabapple, blackhawthorn and cascara.

leaves

female catkins

male catkins

capsule

S. hookeriana

S. piperi


capsulefemale catkinsand leaves

male catkinsand leaves

stipules

male flower

Salix lasiandraSCIENTIFIC NAME

Pacific WillowCOMMON NAME

Pacific willow grows to 12 m in height. Withinsaturated soils, Pacific willow assumes a shrubhabitat, typically with a crooked trunk and aragged, round crown. Within drier soils, itassumes a tree habitat, with a relatively straighttrunk and a more uniform, columnar crown. Pacificwillow is distinguishable by its yellow shoots. Thebark on young shrubs and trees is somewhatshiny and grayish brown in colour. The bark isdark gray and furrowed on older individuals.

The alternate leaves are lance-shaped with a long,tapered tip. The leaves are 5 to 15 cm in length,with the margins finely toothed. Underneath, themidvein is orange-yellow in colour, with theremainder of the leaf whitish and somewhat hairy.Above, the leaf is dark green. The kidney-shapedstipules are borne at the base of a 3 to 15 mmlong leaf stalk. Glands are borne on the stalk atthe base of the leaf.

The flowers are borne on catkins. The bracts arepale yellow, hairy and are shed after flowering. Thecatkins emerge with the leaves on short leafyshoots. Female catkins achieve lengths of up to12 cm, while male catkins grow to 7 cm in length.

The fruits consist of dry, dehiscent capsules thatare fleshy upon initial development. The capsulesare somewhat conical with a constriction at themiddle. They are 4 to 8 mm in length and hairless.

Pacific willow occurs along the margins and withinthe floodplains of streams and rivers. It occurswithin non-tidal and tidal fresh swamps. Commoncommunity associates as a shrub include redosier dogwood, black twinberry,salmonberry, Pacific ninebark, otherwillows, Pacific crabapple, blackhawthorn and cascara.


leaves

female catkins

male catkins

Salix scoulerianaSCIENTIFIC NAME

Scouler’s WillowCOMMON NAME

Scouler’s willow grows to 12 m in height. Its habitranges from a tall shrub to a tree. The bark of

older trunks and stems is dark brown with ridges.Younger stems and twigs are yellowish to

greenish brown with a covering of dense hairs.

The alternate leaves are somewhat egg-shaped, 5to 12 cm long. The tips are pointed to blunt, with

the base tapering. The margin is smooth orsparsely toothed near the base. New leaves are

adorned with downy hairs, more densely so belowthan above. At maturity, the leaves are dark greenand smooth or sparsely haired above, and smooth

or finely haired below. The stipules occur at thebase of the 5 to 10 mm long leaf stalk. The

stipules are pointed and are shed early in thegrowing season.

The flowers are borne on catkins. The stalklesscatkins emerge prior to the leaves. The bracts arebrown to black in colour, 4 to 5 mm in length and

hairy. Female catkins are 2 to 6 cm in length,while male catkins are 2 to 4 cm in length.

The fruits consist of dry, dehiscent capsules thatare fleshy upon initial development. The capsulesare covered with silky hairs and are 5 to 8 mm inlength. They are narrow and conical with a beak

approximately 2 mm in length.

Scouler’s willow occurs along the margins andwithin the floodplains of streams and rivers. It may

be found within non-tidal and tidalswamps. Common community

associates as a shrub include redosier dogwood, black twinberry,

salmonberry, Pacificninebark, other willows,Pacific crabapple, blackhawthorn, cascara and

red alder.


fruiting femalecatkins and leaves

capsule

male flower

Salix sitchensisSCIENTIFIC NAME

Sitka WillowCOMMON NAME

The habit of Sitka willow ranges from that of a shrubto that of a small tree 8 m in height. The bark is darkbrown to grey, with the bark of older trunks and stemsslightly furrowed. New shoots are dark reddish-brownand covered with dense, fine hairs.

The leaves of Sitka willow are 4 to 9 cm in length.They are somewhat egg-shaped, with a blunt-pointedtip and tapering to a narrow base. The margins aresmooth or adorned with small wavy teeth. Above, theleaves are dark green with few hairs, while belowthey are covered with short white hairs that renderthe surface whitish. The stipules are borne at thebase of the 5 to 15 mm long leaf stalks. The stipulesare small, approximately 1 mm in length, and half-oval in shape. The stipules may be shed early orretained throughout the growing season.

The flowers are borne on catkins. The catkins are inturn borne on short leafy shoots. They appear bothbefore and during leaf emergence. Female catkinsachieve lengths of up to 8 cm, while male catkinsachieve lengths to 5 cm. The bracts are brown, hairyand 2 to 3 mm in length.

The fruits consist of dry, dehiscent capsules thatare fleshy upon initial development. Thecapsules are covered with silky hairs and are3 to 5.5 mm in length. They are somewhatconical with a short beak.

Sitka willow occurs along the margins andwithin the floodplains of streams and rivers.It may be found within non-tidal and tidalswamps. Common community associates asa shrub include red osier dogwood, blacktwinberry, salmonberry, Pacific ninebark,other willows, Pacific crabapple, blackhawthorn and cascara.

male catkinsand leaves


Sambucus racemosaSCIENTIFIC NAME

Red ElderberryCOMMON NAME

Red elderberry grows to 6 m in height. Althoughits habit ranges from a small shrub to a small tree,

it typically occurs as a large multi-stemmedshrub. The bark of young stems is greenish to

reddish brown in colour and is adorned with manywarty lenticels. The bark of older stems is

vertically fissured, forming scaly ridges. Thestems are characterized by a central core of pith.

The leaves are opposite and large, consisting of 5to 7 leaflets on a grooved central stalk. The

leaflets are 5 to 16 cm in length, have a sharplytoothed margin, and are borne on 6 to 12 long

stalks. The leaflets are hairy along the veins. Theyare typically lance-shaped, about half as wide as

long. The colour of the leaves turn a necroticyellow in autumn.

The flowers bear 5 petals, are 3 to 6 mm across,and are yellowish to white in colour. They are

contained within individual round clusters whichare in turn organized within a larger round or

pyramidal cluster. The fruits are berry-like drupes.The fruits are more or less round, 5 to 6 mm

across. Each drupe bears 3 to 5 smooth seeds.The fruits are typically bright red; yellow, purple-black, brown and white colour phases have also

been documented.

On the coast, red elderberry often flowers twiceduring the growing season. The first flowering

occurs on stems of the previous season duringleaf emergence in early spring while the secondflowering occurs on stems of the current season

during middle to late summer. The second flowersoften occur on the plant together with the first

berries.

Red elderberry is often abundant within openbroadleaved forests characterized by moist to wet

soil conditions. It is an indicator of rapiddecomposition of forest floor materials remaining

on cutover or fire disturbed sites. Commoncommunity associates within open woodlands

include thimbleberry, salmonberry, snowberry, Pacificninebark, beaked hazelnut, red alder and broadleaf

maple. Red elderberry is an early colonizer ofmoist old fields; a common cohort in these fields

is Nootka rose.

inflorescence and leaf


Sorbus sitchensisS. scopulinaS. aucupariaSCIENTIFIC NAMES

Sitka Mountain AshWestern Mountain AshEuropean Mountain AshCOMMON NAMES

Sitka mountain ash is a native mountain ashcommon to coastal British Columbia. Westernmountain ash, also a native, is more commonwithin the interior of British Columbia. Europeanmountain ash, a non-native as the name implies,occurs predominantly within urban and rural areas.All three species readily hybridize.

All three species of mountain ash display a shrubto small tree habit. Sitka ash, western ash andEuropean ash grow to 6 m, 4 m and 12 m inheight, respectively. The bark of all three speciesis thin, smooth and light gray with horizontallyelongated lenticels. The bark becomes scaly withage. The new shoots of Sitka ash have rustyhairs and are not sticky. Western ash displaysnew shoots that have white hairs and are sticky.The new shoots of European ash have white hairsthat are not sticky.

The leaves are alternate and are divided intoleaflets in all three species. Sitka ash leaves aredivided into 7 to 11 leaflets that are elliptic, 2 to 6cm in length, rounded to nearly flat at the tip, withteeth along the margin of the leaflets from theapproximate middle of the leaflet to the tip.Western ash leaves are divided into 9 to 13leaflets that are narrowly oblong to oblong-lanceolate, 3 to 7 cm in length, tapered to a sharppoint at the tip, with teeth along the entire marginof the leaflet. European ash leaves are dividedinto 9 to 17 leaflets that are oblong to oblong-lanceolate, with coarse teeth along the marginexcept in proximity to the base of the leaflet.

Mountain ash flowers have 5 white petals and areborne in flat-topped or rounded clusters at the tipof a shoot. The flowers appear after the leaves arefully grown. Sitka ash flowers are 6 to 8 mmacross and are borne within rounded clusters; 15to 80 flowers occur within each cluster. Westernash flowers are 10 to 12 mm across and are borne

var. grayi leaf

inflorescence

S. aucuparia

var. sitchensis leaf

S. sitchensis


within nearly flat-topped clusters; 70 to greaterthan 200 flowers occur within each cluster.

European ash flowers are approximately 8 mmacross and are borne within flat-topped clusters;

at least 75 flowers occur within each cluster.

The fruits of mountain ash are berries. Sitka ashberries are ellipsoid to almost round. They areapproximately 10 mm in length and red with a

whitish, removable cast that renders the berriesbluish. Western ash berries are nearly round,

approximately 10 mm long, and a glossyyellowish-orange to scarlet red in colour.

European ash berries are round, orange to brightred, and 10 to 12 mm in length.

European ash has been observed to drop themajority of its leaves during late summer when the

berries ripen; new shoots subsequently emerge,with new leaves and flowers. This new growth

typically does not result in new fruits.

Sitka and western mountain ash are common butscattered within open broadleaved and coniferous

forests. They are especially persistent withinclearings. European mountain ash is commonwithin urban and rural environments, where the

seeds of individuals planted as ornamentals arescattered by birds throughout the landscape.

S. scopulina

S. aucuparia

S. aucuparia

var. cascadensisleaf andinflorescence

var. scopulinaleaf and berries

leaf

inflorescence

typicalflower


Spiraea douglasiiSCIENTIFIC NAME

HardhackCOMMON NAME

Hardhack is a medium sized shrub, growing to 2.5m in height. It is erect and multi-branched. Youngshoots (those that emerge during the currentgrowing season) display reddish-brown bark anddense hairs. Older stems and branches have darkbrown bark that is relatively smooth andlongitudinally shredding.

The leaves are dark green above and light green tograyish and pubescent below. They are oblong tooval and 3 to 8 cm in length. The leaves possessdistinctive teeth from the middle to the end of theleaf.

The pink to deep rose flowers occur within aterminal inflorescence 10 to 20 cm in height andless than half as wide. Individual flowers are verysmall, less than 5 mm across.

The inflorescence turns brown when the fruitsripen. The fruits consist of small pod-like follicles,with the small seeds released when the folliclesplits.

Hardhack is extremely shade intolerant. Withinwet meadows and shallow fresh swamps, it formslarge thickets that often become the dominantcover of the wetland. Within fens, it occurs alongthe margins of drainage channels and seeps, thefresh water apparently ameliorating the acidity ofthe fen, thereby allowing hardhack to persist. Italso occurs as dense thickets at the highelevations of tidal fresh and brackish swamps andalong the shorelines of shallow lakes. A commoncommunity associate within fens is sweet gale(Myrica gale). Within wet meadows commoncommunity associates include beaked sedge, softrush, small-fruited bulrush and reed canary grass.Within swamps, common community associatesinclude red osier dogwood, willows, blacktwinberry, Nootka rose, Pacific crabapple andblack hawthorn.

inflorescence

flower


Symphoricarpos albusSCIENTIFIC NAME

SnowberryCOMMON NAME

Snowberry is a small, erect shrub that grows up to 2m in height. A centre core of pith characterizes young

stems while older stems are hollow. The thin brownbark of older stems peels off as flakes. The shrub isrhizomatous and readily roots from the nodes of its

stems and rhizomes.

Snowberry is heterophyllous; a single plant may haveleaves of many different shapes and sizes. Typically,

the leaves of young shoots (those that emerge duringthe current growing season) are deeply lobed,

displaying a pattern that is rarely reproduced fromone leaf to another. In contrast, the leaves of older

shoots are regularly elliptic to oval, 2 to 5 cm inlength.

The bell-shaped flowers (snowberry is within thehoneysuckle family) are pink to white in colour. Fivelobes extend from the flower tube. The entire flower

is 5 to 7 mm in length. The flowers occur within smallclusters at the end of old shoots.

The fruits are berry-like drupes. They are irregularin shape and 6 to 15 mm in width. Two (2)

relatively large seeds are produced by each drupe.

Snowberry is a common inhabitant of open forestsalong the margins and floodplains of streams and

rivers. Common community associates include redelderberry, Indian plum, beaked hazelnut,

thimbleberry, salmonberry and vine maple.

external viewof flower

section of flower displayingstamens and pistils

leaves and flowers


Thuja plicataSCIENTIFIC NAME

Western RedcedarCOMMON NAME

Western redcedar is a large coniferous tree thatgrows to 60 m in height and 2.5 m in diameter.The crown, symmetrical and narrowly conical inyoung trees, becomes increasingly irregular withage. The principal branches are spreading, slightlydrooping, with upturned ends. Branchlets arestrongly flattened and fern-like, and are oftenpendulous. The bark of young growth is thin,reddish-brown and shiny; older growth ischaracterized by shreds and narrow ridges. Thetrunk of mature trees is strongly buttressedat the base.

The scale-like leaves are 1 to 2 mm in length withsmall inconspicuous resin glands on the outersurface. The leaves, shiny and yellowish-green incolour, occur as opposite pairs, with those of onepair folded and the other not, overlapping in ashingled arrangement resembling a tight, flattenedbraid. The leaves are ultimately deciduous, havinga life of 3 to 4 years; commencing in late summer,branches are conspicuous in possessing green(live) and red-brown (dead) branchlets distally andproximally, respectively.

The male cones are more or less spherical and to2 mm in length. The female cones are ovoid,brown and 12 to 18 mm in length at maturity.Juvenile cones are bluish green. The conestypically have 8 to 10 scales with a small, weak,sharp pointed tip. The scales contain seeds 6 to 7mm in length. The seeds are adorned with lateralwings that are almost as wide and somewhatlonger than the seeds.

Western redcedar grows best on alluvial sites. Itmay also be found on rich dry soils and insphagnum bogs. It rarely occurs as pure stands.

winged seed

orientation ofscales

branch

male cone female cone


needleorientation

scale

post pollen malecones and seed cones

branchand needles

Tsuga heterophyllaSCIENTIFIC NAME

Western HemlockCOMMON NAME

Western hemlock is a large coniferous tree thatgrows to 60 m in height and 1.2 m in diameter.The leader is conspicuously drooping, with theprincipal branches mostly downsweeping. The

lower portion of the trunk in mature trees isbranchless. The bark is reddish brown and smooth

in young trees; it is rough, scaly, thick andfurrowed in older trees.

The needles are flat, blunt-tipped, widely andirregularly spaced, and of unequal length (5 to 20

mm). The needles are shiny dark green andgrooved above, and whitened below with ill-definedlines of white dots (stomata) on either side of the

midvein. The needles are clearly arranged in 2ranks, with a few shorter ones on the upper side

pressed against the twig.

The seed cones are ovoid, 20 to 25 mm in length,blunt tipped, short stalked, purplish-green when

young and golden brown when mature. The scalesare rectangular, tips rounded, and the marginsmooth or faintly toothed. The cones open in

autumn and the seeds are shed gradually. Thecones may stay on the tree for up to 2 years.

Western hemlock is extremely shade tolerant,regenerating well under a

closed canopy. It grows beston organic soils, and is oftenfound growing on rotten logs

or partially decomposedforest litter. It also grows in

full sunlight, and requireshigh soil moisture and a

humid environment for goodregeneration and growth.

orientation ofscales

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