'" ; .

Ecology ofShore Pine StandsInfested WithDwarf MistletoeON SOUTHEASTERN VANCOUVER ISLAND

by E.F. Wass

CONTENTS

•Pog.

ABSTRACT .. _ ..............•...•.••.

INTRODUCTION .

2

3

GENERAL DESCRIPTION OF STUDY AREA.......••••...•• , • •• . • • . •• . ••• • . . •• . 4

METHODS..................................•...................••.... 6

RESULTS.. . . .. .• ••••. .••••• ..••••.. . . . •••• .. .••.•• ..•.•• . . ..•. . .•. .. 7

Soils ..........•......•.....••.......•...••..•.. 7

Vegetation. . . . . . . . . . . . . • . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . 8

Air Temperature ...............•.....•..•...•..•....••............. 11

Dwarf Mistletoe Distribution. . . . . . . • • . . . . . . . • . . . . . . • . . . . . • . . . . . . . . . . . . . 12

Main study area. . . . . . . . . • • • . . . • • • . • • . • • • . • • • . . • • • . . . • • • • • . • • . . 12Orcas Island. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Other areas. . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Dwarf Mistletoe Infection Intensity. . . . . . .• • . . . .••• •• • . • •• • . . .•• . •• . • . • . . 14

Site Indell: and Stand Condition , . . .. . . . .•. 17

Damaging Agents on Dwarf Mistletoe. . . • • • • • • . . • • • • • • . . • • • • . . • • • • • . . • . • . . 17

DISCUSSION AND CONCLUSIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . 17

ACKNOWLEDGMENTS.............••.•••..••..•..• , •....•...•..•.. _ • . . . . 18

REFERENCES.. ... . . .. ..•.. . .. . .•. .. . ... .. . .. .•• . .. . ..••. . ..• ... .. .•.. 19

APPENDICES........••.••..•••..•..••.•••..••.••...•...•..•.••...•.... 21

ABSTRACT

The dwarf mistletoe occurring on shore pine (einw.contorta var. contorta) 10 Coastal British Columbiais classified as Arceuthobium tsugense, a mistletoethat principally parasitizes western hemlock (T5ug3huerophyllal. Shore pine is considered its secondaryhost.

A detailed study of infestations on S.E. VancouverIsland indicated that dwarf mistletoe intensity onthe shore pme was extremely high. An average of85% of trees over 1.4 m were infected and the averagestand infection intensity ranged from 0.7 to 5.1 on a6-c1ass system.

Most infection centers were located in the CoastalDouglas-fir Zone on mountain tops consisting of amosaiC of plant communities of forest on lithosalsand rocky knolls. Vegetation was dominated by firuucontorta var. contorta, Pseudotsuga menziesji.Arbutus menzjesij. Sill.!. scouledana, GaultheriaX!.l!!2.D, Arctostaphvlos columbiana. HolodiS2JsQill:212.r and ArctoS1aphylos ~1illi.

The study showed that A tsugense on shore pineflourishes on habitats separated from A tsugenseon hemlock. Separation of the two would favormaintenance of the physiological differentiationindicated by earlier cross·inoculation experiments.

FIG. 1. Cross.tlalched atM Indialtft dlstribullon ofArceulhobium lli!!I.I!!H: on weSlem hemlock. Number' referto ar., where !,.~ hal bHn found on short pine:1. • Vletoria.sooke area; 2· PtrkS\lilla·Horne Lake area;3· Sprout Lake; 4- eourltnav; &- Texada 1,lInd; 6- s.chelt;7- Malcolm I,land, 8- Terrac:.; 9- Port C~.nu;10- Lund arM;11· Savory I.llnd; 12- Mautelle 1'lInd 13- cones hlend;14- Orcas Island. Box Ind":a1ft study area.

2

L'auteur identifie Ie Faux-qui habitant Ie Pin torduI.e contorta var. contortal Ie long de la cote de laColombie-Britannique comme iltant Arccuthobiumllugens. parasite principal de la Pruche occidentale(Tsuga heterophyllal mais secondaire du Pin tordu.

Selon des releves detailles dans Ie sud'est de I'ile deVancouver, ce Faux'QUi se revele extremement fre­quent sur Ie Pin tordu. En moyenne, 85% des arbresmesurant plus de 1.4 m etaient infectes et I'intensitemoyenne d'infection dans les peuplements variaitde 0.7 Ii 5.1 selon Ie systeme de la classe 6.

La plupart des centres d'infeetion se situaient dans lazone des Douglas latifolies cOtiers au sommet desmontagnes et consistant en une mosaique d'associa·tions de plantes en foret sur Iithosols et sommetsrocheux. La vegetation etait dominee par Pinuscontoaa var. contona. Pseudotsuga menziesii.Arbutus menziesii, Salix scouleriana, Gaultheriashallon, Arctostaphylos columbiana. Holodiscusdiscolor et Arctostaphylos uv....ursi.

8: tsugense sur Ie Pin tordu se trouve dans des habitatsdifferents de ceux de ~. tsugense sur I, Pruche.La separation des deux favoriserait Ie maintien de ladifferentiation physiologique indiquee par desexperiences anterieures d'inoculation croisee.

INTROOUCTION

Hemlock dwarf mistletoe. Arceuthobium tsugensea parasite of considerable importance (2). rangesfrom near Haines, Alaska to central Californiaand is found throughout the coastal hemlock forestsof British Columbia IFig. 11. The principal host inBritish Columbia is western hemlock (llugaheterophylla) but several other tree species areattacked when they grow in association with infectedhemlock; namelv. shore pine (fi..!::!l.!j cootQrta var.conton,). amabilis fir (Abju amabilis), alpine fir(AhW lasjocaroal. grand fir lAb.iu 9WlW1l,Engelmann spruce~ eogelmaoojil. Sitka spruce(~ sjtchens;s) and white pine (finw montjeola)121.

In their classification of Arceuthobjum. Hawksworthand Wiens (18) premised that a species must remainmorphologically distinct when occurring on any ofits hosts. They recognized that the dwarf mistletoeon shore pine occurred in mixture with non·infectedor very lightly infected western hemlock, but theydid not have sufficient reason to classify this speciesother than as A. wgense.

In the Parksville area (Fig. 1. No.2), Kuijt (23) foundseveral mixed stands where either western hemlockor shore pine were heavily infected, but infectionswere not found on the other host. Smith and Wass(40) quantitatively studied the disease intensity onboth hosts, confirming Kuijt's earlier observations.

Smith (39) shOW«! that inoculation of A. tsugenSCfrom shore pine on western hemlock produced onlyone definite swelling and no shoots (abortive type ofinfection). In contrast, 22.5% of seed of A. tsugensefrom western hemlock resulted in infections onwestern hemlock and all swellings produced aerialshoots. On other hosts, A tsugense from shore pinegenerally produced more globose swellings thanA. tsugense from western hemlock. Field inOOJlationexperiments, presently underway (381. have producedthe same results as the plantation inoculations.

Dwarf mistletoe on shore pine was first reported in1906 by Rosendahl and Butters on Vancouver Island.It was reported by Kuijt (23) on the eastern side ofVancouver Island, as far north as Comox, and nearSed'lelt on the mainland and by Hawksworth andWiens (18) on Orcas Island, Washington. A tsugenseoccurs on shore pine in less than half of the latitudinalrange of A lSugense, being absent south of the SanJuan Islands and in Alaska (15, 18).

Most of the infested stands occur in elevations ofup to 5OO·m a.s.1. in the Coastal Douglas·firBiogeoclimatic Zone (22). Infestations in the CoastalDouglas·fir Zone consist of extensive pine stands

3

FIG. 2. Brooms end btench swellings eeused by ~ 1M"'.on shore pint et Malcolm Islend.

with no, or onlY lightly, infected western hemlockpresent. In contrast, within the Coastal WesternHemlock Zone (Fig. 1, Nos. 7, 8 and 91, standsconsist mainly of western hemlock, western red cedarand stunted shore pine (Fig. 2). The western hemlocktrees are heavily infected. The few shore pine infectedhave a very high infection intensity rating and aredlaracterized by well-defined fusiform (spindle­shaped) swellings.

On the southern tip of Vancouver Island, heavilyinfected stands of shore pine are found on rockyknolls and mountain tops even though the majorhost, western hemlock, is either not present ornot infected. Is A. tsugense on shore pine an ecotypephysiologically adapted to a localized habitat? Toaid in answering this question, a survey was designedto determine the distribution of A. tsugense on shorepine and to define the ecological d1aracteristia ofthe dwarf mistletoe infested stands and their habitats.

6

FIG.5. Logging 01 Douglas-fir on rocky terrain near Soake.

METHODS

Mountains, located on topographical maps and aerialphotographs, were visited to observe whether infec­tion of dwarf mistletoe oa:urred on shore pine. Asinfection foci were identified, the search radiatedoutward to new areas. Shore pine and western hemlockalong the route to the mountain tops were checked forp:,. tsugense. Shore pine stands in bogs were alsoexamined for the presence of A. tsugense. Theboundaries of infestation centers were transferred toaerial photographs (1; 15,840) and areas were calcu­lated using a planimeter.

Once a shore pine stand was located, the followingdata were collected: location, elevation, age ofstand, whether infected with dwarf mistletoe, andthe extent of infestation. Eleven infestation centersand one non·infested area in shore pine, and oneinfested area in western hemlock were selected formore intensive study (locations 1-13, Appendix 1).

A representative 0.04 ha plot was established in eachof these stands.

Soils were described from one or more pits. dug ateach plot. Profile descriptions follow the Canadian

Soil Classification System (6). Soil texture wasobtained using the Booyoucos hydrometer method(4). A field pH meter lCorning Glass Works, Model 7)was used to determine the pH of soil horizons usingHtl and CaCl2 (271. Munsell color charts were usedfor soil color t29l.

Species cover and abundance was an estimate usingthe scale of Braun-Blanquet (Appendix 1111 (5).Rocky knolls within the plot were examined as partof the plot, and by themselves as a separate sub-plot.

Air temperature was measured in standard Stevensonscreens with two max-min thermometers in Plou6 and 7. Max -m in thermometers were also placedbelow the litter layer and on an open grassy slopebetween these plots. Records were taken once aweek from July 23 to Nov. 5, 1973. Relative humiditywas recorded in the two plots for 8 12- hour period(6 a.m. to 6 p.m.) on July 31, 1973.

Each host tree taller than 1.4 m was rated for infec­tion intensity by visually dividing the crown intothirds and scale rating each third (17). Trees lessthan 1.4 m were excluded because of the slightchance of infection of such a small target. The

5

Stll__

Go....I•• (,'/il ",""cto",-

"W,lli.... Hqd 12l

"&dIt< lilY III

'",... lok. j41Sh...,n,

'"Sook. l ..... (5)

."J..,k l ...... 161

,..b<c.n I7l.-'"a.... 0 .... (II

on. in ...",.yod tUM.

Cl...... lic"~ .-. d.na IOf atlll

,- Wilt< .....,(KOIII*I1

TABLE I . Ch"'tllC ....r. {oCI

,.. "'f~ ,-"'-' temPer Coolest ......

,~,

11.... 1.....'...... W.......OI ......Ih

'w'wept.li....

...... _1PI'l WI'tltsl:

..............th

~..Mull Dnnt """"'"

-.,{eml.&!

_ ........th

"'''""',32.8Medltl"_'"

D~

26.9

"''' .. '"10.1 IS.l

' •.6 c..'"

MedilllT_..

'''' ""

24.4 T'_lloontl

15.7" ,,, 21.3

f,_ilio""

" '"'U U

".,

."

"23.6

T'''''itio",,1

'"" "."

11.2"'"

21' ,.,

T,.... itiotl.1

'''' "

loWititow

" '"lHI

21.8,..,.. '""'" M.iti_

"14.5,.,

" '" <.,

,,., .. 14.3" '"3320

aeyll". (81!! 75 em <ton9",

• ion. (Fit- 11). I climatic IUtb.1 lOCil1O/l 0

r

co...,..... WUTlIIN HU'lOC~

M..TtCZONESBIOGEOCl.1

DO!JGlA$-"'"eo"ST"~

g."UIl SUIo«lNf:

'0.'",

--.' ,

P leN (33)).. rtudy Btllll l,lter Be

"-Atic lones 10. biogeoc ,,,_Map shOWIngFIG. 4.

6

FIG.5. Logging 01 Douglas-fir on rocky terrain near Soake.

METHODS

Mountains, located on topographical maps and aerialphotographs, were visited to observe whether infec­tion of dwarf mistletoe oa:urred on shore pine. Asinfection foci were identified, the search radiatedoutward to new areas. Shore pine and western hemlockalong the route to the mountain tops were checked forp:,. tsugense. Shore pine stands in bogs were alsoexamined for the presence of A. tsugense. Theboundaries of infestation centers were transferred toaerial photographs (1; 15,840) and areas were calcu­lated using a planimeter.

Once a shore pine stand was located, the followingdata were collected: location, elevation, age ofstand, whether infected with dwarf mistletoe, andthe extent of infestation. Eleven infestation centersand one non·infested area in shore pine, and oneinfested area in western hemlock were selected formore intensive study (locations 1-13, Appendix 1).

A representative 0.04 ha plot was established in eachof these stands.

Soils were described from one or more pits. dug ateach plot. Profile descriptions follow the Canadian

Soil Classification System (6). Soil texture wasobtained using the Booyoucos hydrometer method(4). A field pH meter lCorning Glass Works, Model 7)was used to determine the pH of soil horizons usingHtl and CaCl2 (271. Munsell color charts were usedfor soil color t29l.

Species cover and abundance was an estimate usingthe scale of Braun-Blanquet (Appendix 1111 (5).Rocky knolls within the plot were examined as partof the plot, and by themselves as a separate sub-plot.

Air temperature was measured in standard Stevensonscreens with two max-min thermometers in Plou6 and 7. Max -m in thermometers were also placedbelow the litter layer and on an open grassy slopebetween these plots. Records were taken once aweek from July 23 to Nov. 5, 1973. Relative humiditywas recorded in the two plots for 8 12- hour period(6 a.m. to 6 p.m.) on July 31, 1973.

Each host tree taller than 1.4 m was rated for infec­tion intensity by visually dividing the crown intothirds and scale rating each third (17). Trees lessthan 1.4 m were excluded because of the slightchance of infection of such a small target. The

A stand infection index for each 0.04 ha plot wasthen calQllated by summing individual tree ratingsand di .... iding by the total number of host trees.

bare bole was included in the bottom third of thecrown. Each third was rated as follo~:

o "' No mistletoe signs or symptoms present1 • 1%·50% of the crown third infected2 • 51% or more of the crown third infected.

An infected bole was counted as one infected branch.Brooms were rated on the basis of the crown area,with a "2" rating given if more than 50% of thecrown third was involved.

7

Stand Infection Index

o0.1·2.02.1·4.04.1·6.0

healthylightmoderatese....ere

The rating for each third was summed and infectionclasses were determined for each tree. as follows:

Summation

Where residuals occurred in the plot. they wereexcluded from the stand infection index. The inci·dence of infection was based on the number of li.... ing.infected trees as a percentage of the total number oflive trees over 1.4 m high.

o1-23-'5-6

healthylightmoderatesevere

A simple linear regression analysis using the leastsquares method was employed to test variousrelationships between average plot mistletoe rating.average age of stand and percent of trees infected.The regressions presented (Figs. 15. 16, 17) werethe best among those tested.

RESULTS

FIG. 6. X.ie habit flllloribl. for snore pil'lfl succeWon.lCirky Hill. Plot 13.

Soils

Shore pine stands studied in detail were located intop or upper slope positiQrls, with the exceptionthat Plot 4 (Appendix I) occurred on a mid slope.The land type was mainly rock outcrop with a fewplots on colluvial slopes. Slope ranged from 1 to34% in the shore pine plots and 40% in the westernhemlock plot. Hygrotope class ranged from mesicto very dry for the shore pine stands studied indetail (Appendix I). The western hemlock plot hada hygrotope class of wet.

A thin mantle of glacial till, colluvium or a mixtureof both covered most plots (Table II). Aeoliandeposits were found on Ragged Mtn. In the westernhemlock plot on Glinz Ck.. the parent material wascolluvium over coarse alluvium.

Two soil great groups were encountered· SombricBrunisols and Dystric Brunisots (Table Ill. Subgroupsof the great groups found in the study were Drthic,Degraded and lithic.

All the soils examined were medium to coarsetextured, ranging from gravelly sandy clay loam tovery gravelly loamy sand. The soils were strongly tovery strongly acid, the acidity usually increasing withdePth.

Soil profile 1Ob, classified as a lithic SombricBrunisol, lacked a Bm layer, the C horizon directly

8

TABLE II c.....tlC••oonO. 1001 Il'O..... 'OO ._1>1<>I- ProM. So~ _ ..fOCM._ - So~~C"" t .." ..,01 l.n.. " pH_..., 0....,01 11- - --- Irom..-,t! -~, -- -- -~ Iancll"' ....

""'.... Ie"" ....' ..,01 -, ,-, =,O....._Oy.."c " s.loI l' ~., 11....lly ....0. ct.. " " " GTIR

8''''''101 --, Oqll", Oy.",e 8'''''''01 " Arbulul SoI.1 '" ~rv if....II. undv " " .. C/GT/R

"-

, lilt".. SomDtOC 8'"",001 " IIlIy'....-.""". '" _,. gr ...oIly.....,V " " " ='".~, "-

, On'''c Oy.r", 8.......... ",... 10.' V."'. wnty ....... " " " C1GT'A

• • L""oe $omll.."_..... " Eurhyl\t1'l ...... '" 91'....11,. loMI'I " " .. '"orlgooom

, 011"'" 0,,",,0 8,un,...1 " ~III ", ..rv go .... II. 10"" " " " '"~."-

, • CleI'..-lOvo"", " Ahyhcl..dollll>u. ""J! ._'Iv~_ " " .. E,GT IIBn"..,101 trq,>otlu.

, 0._ !)y... ", a'...._ " ,... '" ..~lv_V_ '" " EJGT II

, Ofll,,< Somb"c 8<.." ..... W ~loC~ I'olv"'''''''''' 1030- ....1',._,. ...... " " " ~A

"",..,tum

• Lith", 0,.",,,,, B,unilol PI ("'''ynCHum ." ••r. V, ..,II. wndv " " " '"<><091""'" "-

, Orttu" 0."'"" BrulUooI " ,... '" -v .._tv ....... " " " ClGTiR(0 .....,._

, 0,.."", 0.. .."" Bn..noool PI E"rfIvl\t1'l...... .., ~._v .....v" " " ~."._- __v-, 0""", Somb<oc Brun,fOl " Solol 40.0' ..rv 1I' •••Uv...oov '" '"

,., CIGTfA--" Or.hoc Oy.."c 8'un,ool " Ad,u'u. 850- "e'~ " .....lIy '''..... " " " ClGJGT/R

Eu'hYncf>",m",_

, l-,'hoc $<Hnb<oc 8<u_ E.........l-Atc~....ylDo '" -v ............ wndy " " " CJGTfR

u........ -" l-<thoc Oy.1lOC 8,,,,,,.,, PI s.l. '" .............1'_ " "

., ClGTfIl

" O"hic Dy"'1C 8,un,ooI PI s..I.' V""'lUum 890' .",y i'_"Y >II' " ",., CJGfGTfIl

" ••lum --" L,th,c Oy'ifIC a,un,,,,1 PI ·50'" V"""',um '" !I'...lIy.....,~ ""m ,., "

., ClOT/II

" ..tum

y p,._.- • c· col..........A ..........m

V • a _ad< """ relCl>«l G·tl~fkw'"Gl'III_'I,P

11* bodffX.[a ...",.... Iw,nd_l

underlaying the Ah. Because of the lack of a 8mlayer, this soil might be classified as a Lithic Regosol.It was developed under a grass cover. Representativesoil profile descriptions are included in Appendix II.Including Lithic soils (bedrock within 50 em),bedrock was located close to (within 1 m) the surfaceof 13 out of 18 of the profiles studied.

Vegetation

Shore pine on mountain tops occurred in a mosaic of

forest communities on lithosols intermingled with

rocky knolls. Two plots jNos.12 and 13) were in theCladonia·Douglas·fir association of the WesternHemlock 8iogeoclimatic Zone. The western hemlockplot (No.6) was located in the Sword fern associationand the remaining 10 plots were in the Salal·lichenassociation of the Coastal Douglas·fir BiogeoclimaticZone (9).

Lithosols were characterized by a tree cover, heavyshrub layer and moderate herb-moss layer (Fig. 7).The lichen layer increased in abundance with decreasein density of stand and increase in exposure. Incontrast, the rocky knolls were characterized by a

9

FIG. a. Ro<:k.y Knoll dominatld bV moSS8S 8l'1d liehenl,Bluff Min. {Plot 91. V

lack of tree cover, a scant shrub layer and groundvegetation dominated by moss, grasses and lichens(Fig. 8).

The shrub layer in the forest on Iithosols rangedfrom 1(}.8Q% cover and was characterized byGaultheria shallon. Arctostaphylos columbiana.Berberis nervosa. Arctostaphylos .l.I!lI:..!.!.!. &u:iI.

>FIG. 7. FOl"est on lithotol with .."I groul'ld coYIt".

R899Id Mtn. (Plot 5).

Structure of the forest commumtles depended onthe stand history which IS dominated by fire. Thetree stratum was three structured. The upper layer,overmature Douglas-fir (over 200 years old), occurredscattered throughout the area. Below this was alayer of mature shore pine and Douglas-fir, varyingfrom an equal mixture to the complete absence ofDouglas-fir. The immature tree layer was dominatedby shore pine with Douglas·fir. Arbutus menzies ii,and Si.!ils. scouleriana. The stands differed greatlyin their stage of succession.

10

FIG.9. Heavy growth of lichens on infected shore pine. Aerie] stloon of~.. tlU9!nse I.rrowl.

gymnocarpa. Pachystima myrsinites and Holodjscu$discolor (Appendix III). Salal growth was poor (30-60em taU) in all plots except 12 and 13. which werein the Western Hemlock Biogeoclimatic Zone. Inthese, salal was 90 to 120 em high and Arctostaphyloscolumbiana was replaced by vigorous VaccjojumQll.tl.lm. Herbs included Goodyer3 obloogjfQliaTrientit1is lat,folia, Erythroniurn oreganum, Hjeracjumalbjflorum, DodecatheQD hendersooji. Habenariaunalascensis, Listera cordata and ~ J.l..W.ni.Mosses in the forested area were abundant, but lessdiverse than on the knolls.. Eurhvnchjum oreqanum.RbytidiadelphU$ tTiquetris and Dicranum howel!jjwere most common. A lichen characterizing theseshore pine stands was Pelt,ger, aphthosa. Shore pinewere heavily covered with lichens (Appendill IV)(Fig. 9), predominantly Alectorja sarmentosa.

Rocky knolls, which ocwpied from 2 to 70%of the plots, were characterized in the shrub layerby Gaultheria shallon, Holodiscus discolor andArctostaphylos uva-ursi (Append ill II). The herblayer included an abundance of grasses, mainly£l:i!lli.u ~, Festuca !!.!.!2!:J and .A.i!iI praeCOII,with Achj!Jea milljfolium, Cryptogramma .k£.imiand Selaginella wallacei. Mosses included

Rhacomitr!um canescens, Dicranum fUsceSCfOS.

Polytrjchum junioerjnum and Rhacomltflumlanuginosum. In comparison to the forest on lithosols,there was a greater variety and abundance of lichens;namely, Sterocaulon tomentosum, Cladon!a~Cladonia bellidiflora, Parmelia saxatilis, Parmelia~ and Umbilicaria hirsuta.

The western hemlock infected plot was representedin the tree layer by Tsuga heterophylla, Thujaplicata and Taxus brevifolia. Gaultheria shallon,Rubus spectabili$ and Vaccinium parvifolium werethe most prevalent shrubs. Herbs includedPolystichum munitum, Pteridium aguilinum, Tiarellatrifoliata, Achlys triphylla, lactuca biennis andMitella oentandra. Moss layer was represented byRhizomnium glabrescens.

Shore pine was ellamined in lowland bogs developedon deep material deposited during the retreat ofglaciers. They were in the fin..!.!j·Gaultheria-Ledumassociation (34, 35) dominated, in the understory,by ledum groenlandicum, Gaultheria shallon,Sphagnum capillac:eum, Vaceinium oxycoccus andEmpetrum nigrum.

11

Temperature and Relative Humidity

Maximum temperature averaged 2.2'lC nigher in theshore pine stand than in the western hemlock stand.The Iverage minimum was ,oC higher in the shorepine stand. Maltimum litter temperatures averagedGOC higher in the shore pine stand than in thehemlock stand. Maximum temperatures averagednoe higher for liner on open rocky slopes than onfore$ted slopes. The average minimum temperaturewas a.SOc higher.

Absolute millimum and minimum temperaturesreached at Glinz Ck. and Hill 22. between July 23and October 26, are shown in Table t' I.

'00

"

,: "i

".

._~~

'.'.•..••,,, ~._---

./". ---'. .-,'-

".-. ",

'---', ..­. .V

~(L"T'V(

MU"'OIlY

"

"

" .,I

• I

TABLE III. Temperature data from shore pineforest, western hem lock forest andopen slope sites. "

H£""'-Oell "....c ----­_~( '!Hl ITAlCl _

•Glinz Ck. Hill 22western shore open

hemlock pine stope...•.•................0C········ ..........•.•.•

Figure 10 shows air temperature and relative humidityin relation to time during a 12· hour period on July31,1973. Maximum temperature was reached at 1600

Stevenson screenmaximumminimum

Below littermaximumminimum

271

244

304

404

54+

6

01·00 0f000 '0.00 '1'00 "'00 "'00 ",00

T"'Il"1lS1

FIG. 10. Aeletive nurniditv end tlllTlperlilure lor west.nhemlock end shore pine silMOn JulV 31. 1973.

hr for both sites, with a difference of 20 C. Relativehumidity was 96% for both sites in the morning.The minimum relative humidity was reached at1500 hr in the shore pine stand, an hour earlierand 10% lower than in the western hemlock stand.

TABLE IV· Distance between infested shore pine stand and nearest infested western hemlock stand.

W. hemlock infestation centers

Glinz Ck. (No.6) JjlBamberton Provincial Park (No. 26)Iron Mine Hill (No. 27)West side of Sooke Lk. (No. 29)Mile 6 Boneyard Lk. Ad. (No. 37)2 miles north of Sooke A iver Rd.and Boneyard lake Rd. crossing (No. 38)Junction of Phillips Rd. andSoake Rd. (No. 50)3 miles north on Phillips Rd.(No. 51)

aJ location numbers from Figure 11.

Nearest shore pineinfestation center

Hill 22 (No.7)Jocelvn Hill (No. 24)Mt. Matheson (No. B)Mt. Healy (No. 281J!2 mile N.W. of Boneyard Lk.Hill 25 (No. 36)

Mt. Manual Quimper(No.4)

Mt. Manual Quimper(No.4)

Horizontal Verticaldistance elevation

difference difference(km) 1m)

0.3 917.7 3357.6 2132.3 5361.6 2430.8 213

5.5 512

4.5 490

12

Dwarf Mistletoe Distribution

Main study area

Fifty-one localities were examined within the 789 km2

study area (Appendix V and Fig. 11).

Twenty·seven infestation centers on shore pinewere found in the study area, 24 on mountain tops,1 on an island (Fig. 11, No. 19) in the center ofShawnigan lake, 1 in a bog (Fig. 11, No. 471 and1 on a rocky knoll on the edge of Matheson Lake(Fig. 11, No. 451. Eight infestation centers on westernhemlock were located, all in valley bottoms (Fig. 11).Seven stands of shore pine on mountain tops, 3 inbogs and 1 on a gravelly outwash plain (Fig. 11, No.33) were examined and found to be non-infected.Area of infested stands ranged from a small area(few individual shore pine) to 165 ha (Appendix VI.

Infested shore pine stands located on mountaintops ranged from 722 m a.s.l. (Mt. Healy) to a lowof 274 m a.s.l. at Mt. Matheson. The three infestedareas not found on a mountain top had elevationsof 116 m (Memory Island), 351 m (Charter's bog)

and 24 m (Matheson Lake). Western hemlock standsthat were infested ranged from 24 m a.s.1. at SookeRd. and Phillips Rd. Junction to 244 m a.s.1. atGlinz Ck.

Of all these areas examined nOt once did A. tsugenseon western hemlock grow in association with orclose to infected shore pine. Except for two coilPC'tions (Memory Island and Matheson Lake) there wasno elevational overlap between the two host/speciescombin... tions. The dist ...nce and elevation differencesbetween the two host/species combinations areshown in Table IV.

Five bogs were examined for A. tsugense on shorepine (Appendix VI. They ranged in elevation from30 m to 488 m and tree ages ranged from 55 to 127years. Dwarf mistletoe was found in only one bog,on two trees only. These were heavily infected andstunted (Fig. 121. The age of shore pine averaged 81and 127 years for infected and non·infected trees,respectively. All four western hemlock trees present(153 years oldl were found to be non·infected. Alltrees had fire scars and burned bark.

T

SUAVEYEOPOINTS

Cl ......TICSTUIOHSIT...L(' I

.. NIl SI'IOfI( 'IH(

<o 41 "'~o

.. IN'ECTED ...ESTEIlN >!IMLOC"

• 'NFfCllD SHDIlE ""E

10 ~ ...~-~,

,

PE"'NSUlA".

".

FIG. 11. Survey poInts checked for dwarf miJtI~oe. LOClllions••1_lions and lill! of inf,slecl area for individual survey poInts.re given In Appendix V.

FIG. 12. Infected ,horl pinl hlrrowl in Chart.'s bog.

Orcas Island

The only recorded parasitism of shore pine byA. tsugense in the U.S.A. occurs on Mt Constitution,Orcas Island. Mt. Constitution consists of Triassic­Jurassic sandstones and siltstones (26) and has beenaltered by glaciation, both by contouring and deposi­tion of glacial drift.

Because of the rain shadow effect of the Olympicmountains, the summers are dry and relatively0001. the winters wet and mild; the frost-free periodis long. Mean annual precipitation is 46 an. Thecoolest month has a mean min temperature of OCc(January) and the warmest month (July) a mean maxtemperature of 22.50 C. Elevation has a primaryeffect on the local climate 1111.

Franklin and Dyrness (ll)51ate that plant communitiesfound on the east coast of Vancouver Island are

13

FIG. 13. Stunted infected shorl pinion summit ofMt. Constitution, Oreal Island.

sim Har and that the Coastal Douglas-fir Zone is relatedto the Puget Sound Area. Shore pine and westernhemlock stands are located on Mt. Constitution,where the higher elevation results in a greater supplyof moisture. The shore pine are found in the xericsites on shallow gravelly soils of glacial and colluvialorigin.

A tsugense was found on the upper slopes ofMt. Constitution from 671 m to 734 m (the wmmit).The stand oonsisted of mainly shore pine, 70·BOyears old, with scattered secondary growth Douglas·fir. Shore pine on the summit were stunteti (3mto5 m tall) due to heavy mistletoe infestation, shallowsoils and exposure to high winds (Fig. 13). Thestand oonsisted of a mosaic community similar tothe main study area, although knolls were less exposed.Vegetation was similar, except for a higher cover ofChimaphita umbel lata

14

FIG. 14. Infected _lItern hemlock .mong h_ily infected$hor, pine. Mt. Constitution, Oren Island.

One young western hemlock was found in theinfested shore pine stand. Although surrounded byheavily infected shore pine, it had only a singlebranch swelling (Fig. 14). A small patch of moderatelyinfected. 58-year-old western hemlock was foundbordering the pine stand in a hollow at mid·slope.

Other areas

Some mountains located north of the study afeahave similar vegetation communities. Mt. Benson(1019 m) and Mesachie Mtn. (396 mi. containingshore pine to the summit, were examined. Kojima(21) found an Arbutus menziesii community similarto the study area, containing shore pine on theextremely dry sites in the Coastal Western HemlockZone, on the east side of Buttle Lake. Shore pinewere checked in the above locations but were foundto be non-infected.

Dwarf Mistletoe Infection Intensity

Thirteen stands were studied in detail, 11 of infestedshore pine, 1 of infested western hemlock and 1 ofhealthy shore pine. The composition of shore pinein the plots ranged from 40% to 96% !Table VI.

TABLE V SI¥Id compC)iilion Ind ~rc.nlof U", Infected 10.04 heCl:..e ploul.

p,,, Location ,,,... .,.,..- _w.WRC~ Weswrn ..... y- ""'" """. Weslern Western TOlil

~. ",. I" """..... pM PM """..... """Ioc' .-• infecled • ;nfllCled

• •MI. H,lmck,n ,as , , 96.' 77.S ,.,

, MI. W,1l1 S! ,. .. 42.9 43.8 '", Ml W,III ., \I , 68.' 6J.' ..• Ml Menu,1 26 IS 63,4 96' ..

QuimPlf, RIIPd MIn. SS JO ".7 100.0 6S, Glin2 Ck, ., 95.9 61.1 ..7 Hill 22 ., 11 , 61.7 976 6', MI. Mllheson ., 6' ".0 100.0 '05

9 81ulf Min. " 1J 81.9 100.0 "" Ml Work 71 " " 49.0 88.6 'OS

\I .".. 100 52 .... 100.0 '"" Ml MIlIU'" '52 ,. 7 .. , 00 J9'

1J K"byH,lI ,., , , 93.5 49.2 'J9

" WRC • WIlI"n rid cedar

15

TABLE VI. Infection intensity rating and age data for each plot.

Plot Avg. infection rating Avg. Infection Avg. Avg,no. by crown class total class age of age of

rating immature residuals0 Co S stand

2.7 2.5 2.7 1.3 2.1 Muderate 40.2 96.0

2 1.8 1.5 0.3 0.2 0.7 light 23.0 98.3

3 3.4 5.1 3.3 0.0 '.0 Moderate 79.6 19,6

• 3.6 5.1 5.9 3.5 5.0 Severe 61.0 61.0

5 5.2 5.3 '.6 5.' 5.1 Severe 62.7 62.7

6 4.0· 3.0 1.4 1.1 1.3 light 39.0 113.0

7 5.4 4.7 3.7 3.2 4.4 Severe 62.0 62.0

8 6.0· 3.5 3.6 4.5 3.6 Moderate 41.7 66 + rot

9 4.9 5.0 4.1 4.3 4.6 Severe 57.3 99.0

10 2.7 2.2 2.2 2.6 2.4 Moderate 27.8 68.0

11 4.8 '.6 4.7 5.0 4.7 Severe 78.5 78.5

12 0.0 Healthy 64.6 64.6

13 1.0 1.0 0.9 0.2 0.9 Light 41.0 41.0

·Contains residuals only; therefore, no dominant trees included in the Ivg. total rating.

Average age of stands ranged from 23 to 80 years(Table VI). The stands were even-aged (age rangetess than 5 years) though. in most cases, residualswere scattered throughout the immature stand.

The average age of stand correlated significantlywith the percentage of trees infected IPcO.ooli.with 84% of the variation accounted for by theregression (F ig. 15). Based on the regressionobtained, 69% of the stand would be infected atage 30. 86% at 50 years and 100% at age 76.

Since residual infected shore pine were presentat the formation of new stands. the duration ofinfect ion is considered the same as the stand age.A significant correlation (P< 0.0011 occurredbetween average age of stand and average plotmistletoe rating, with 79% of the variation accountedfor by the regression (Fig. 16). Stands at 35 yearswould have an average rating of 2.2 and at 70 years, arating of 4.8 (Fig. 161. The time for the plot mistle·

toe rating to increase by one class averaged 15 years.

There was a rapid increase in the percentage of treesinfected with increasing average plot mistletoerating . 46% of the trees were infected in plotshaving an average mistletoe rating of 1.0, and 100%infected for those with a rating of 5.5 (Fig. 17).Correlation between percentage of trees infectedand average mistletoe rating was highly significant{p~0.00' J, with 95% of the variation accountedfor by the regression.

The western hemlock infected stand had anaverage stand infection index of 1.3 with 61.7%of the trees infected.

Plots having a tight stand infection index showeda trend of infection rating increasing with treecrown class (Table VI). Once stands reached amoderate or severe index, infection rating forsuppressed and intermediate was as high as thedominant and co-dominant trees.

•,i

.0

'0

•

16

•

i·",lUIo'l~-~UC

,·o.~.

'."--:-:--0-:-:-0-----;;;;---:::--"'--,0,-::::-'-,:':""::'461910 20 :1040llO&OIOIOO

AVO. AGf Of ST~O - noUls

FIG. 15. Relationship betWllen percentof trees inlllCtlld end averagllage of stand.

;:oOOfl'4X-O.zue,,0 ••

'. "--c'o----:,------:,------:,------+.,------+.,-----=---=-~.,0 20 :lO ~ ilO ~ ~ ~ ~

_ loGE Of SUllO - YEo""'S

• 1"'•

•

FIG. 16. Relationship bl1tween average

plOT mistletoe fating end average age of$tand.

"Q••0••, .0

•••, •, •'0·••,,'0

••

j. ~364110.(•• ,l •• 4,0

"0114

FIG. 17. Relationship between percentof trees infllCtlld end average mistletoeplot rllting.

AYG MlSTLErO( PlOT RUIJl6 PLUS 10

Site Index and Stand Condition

Site index (height in meters at 100 yearsl forDouglas·fir ranged from 15 to 30, with an averageof 20 (poor growing site) (9). The 3Yerage siteindex for shore pine was less than 18 (poorgrowing sitel.

Because of the poor sites and the damage inflictedby mistletoe, the shore pine stands were very"ragged" in appearance (Fig. 181. Dead trees rangedfrom 1.5% to 29.2% of all trees within the plot.The highest mortality occurred in Plots 5 (RaggedMtn.I, 9 (8luff Mtn.) and 11 (Mt. Jack). Blowdownand broken tops ocwrred extensively in theinfested areas studied.

FIG. 18. Smellftt tree lound infect.:! In tn. study .... was51 em tIIll (from root col"r lalTowll, glOWing on I rockoutUl:lP with its roots ...,b«id.:! in ,hi rock O"ft'icft. It w.38 V_S of liCL

17

Damaging Agents on Dwarf Mistletoe

Of the 27 infested areas studied, hyperparasiteswere found in two areas..

A fungus, Cylindrocarpon qillii (28), was found inPlot 7. Aerial shoots of dwarf mistletoe were heavilyinfected, many being girdled and killed. This host!hyperparasite combination on shore pine has beenpreviously reported by Kuiit (24).

A fun~s, ~ macrosoora, was found onA, tsugense swellings 0f1 western hemlock on thewest side of Soake lake (Fig. 11, No. 29) and iswidespread throughout the range of western hemlockdwarf mistletoe in British Columbia 1121. Symptomsare resinosis, cankering and girdling of infected hostbranches.

$hare pine dwarf mistletoe swellings were gnawedby red squirrels lTamiasciurus hudsoniQJSlanugino$Us). Feeding was restricted to the bark inthe vicinity of the infection. Squirrel feeding hasbeen previously reported by Baranyay (1) on lodge­pole pine attacked by A americanum in CentralBritish Columbia and in the Rockies of Alberta,but not on infections of A tsugense on shore pine.Infections on western hemlock showed no signs ofsquirrel feeding.

DISCUSSION AND CONCLUSIONS

A tSU9!!nst on shore pine is more extensive thanpreviously~ealized but is restricted to certain habitatswhere shore pine is essentially the climax species.Infected shore pine occur in a lithosol -rocky knollmosaic and in xeric habitats, both in the Coastal­Douglas·fir Biogeoclimatic Zone and the dry subzoneof the Coastal Westef"n Hemlock BiogeoclimaticZone. The he3YY concentration of A. tsugense onshore pine in the study area reflects the abundantclimatically and edaphically xeric habitats which,with the help of fires and logging, are favorableto continuitY of shore pine.

Geographic distribution and habitat are differentfor A WRense on shore pine than those for theparasite on western hemlock. Microclimate, mainlytemperature, is different between hemlock andshore pine infested stands. In the Coastal Douglas·firZone and the dry subzone of the Coastal WesternHemlock Zone, western hemlock develops only as anedaphic species on subhVgric habitats and does notaeon on xeric habitats (22).

The size of the infested area reflects the stand historyand topography of the area. Where fire was severe and

the terrain less of a mosaic (forested and rockoutcropsl. very few residual infected shore pine werefound that could re-infect the secondary growth.Where the moontains were broken up with manysubpeaks and where a patchy burn occurred, moreinfection centers were found, and a larger area wasinfested.

The older and more extensively infested foreststands were found on moontain tops having a mosaiccommunity of rocky knolls and forest on lithosolson glacial till, colluvium or a mixture of the two.Shore pine could have been more extensive in thisarea during the early post glacial period, as it is ableto thrive on recently disturbed terrain. Thus,A. nugense on shore pine may have been moreextensive, and only in later years largely restrictedto mountain tops.

Current spread of A. tsugense on shore pine hasbeen from the mountain top to lower elevationareas adjacent to the stand. This spread probablyhas accelerated with man's intelVention by loggingand with increased fires. Infection in isolated locationssum as Memory Island, Charter's bog and the edgeof Matheson lake could indicate a long distancedispersal, beyond the normal dispersal distanceof the dwarf mistletoe, for which birds could havebeen responsible.

An average of 15 years is requ ired for the standinfection index to increase by one class. This isvery close to the 14 years determined by Hawksworthand Hinds (16). The percentage of stems infectedat the younger ages is much higher than that foundby Hawksworth (14) on lodgepole pine infectedwith A. americanum. Intensification of dwarfmistletoe in shore pine stands is very rapid. Asurvey carried out by the Canadian Forestry Servicegives an average infection rating for infected westernhemlock of 2.95 for stands having an average age of62 years. In the present study, shore pine infectedwith A tsugense had an average infection rating of4.08 at the same age.

Dwarf mistletoe causes volume loss and mortalityin moderately and severely infected forest stands(21. and control measures may be consideredworthwhile for those shore pine stands on deep,relatively productive soils in the study area andfor other infected shore pine stands in the CoastalDouglas-fir Zone with a potential for commercial

18

wood production (e.g.• Parksville-Horne lake area).The rapid intensification of mistletoe in the shorepine stands studied means that sanitation measures(removal of infected trees) can not be applied success·fully to stands over 20 yeats of age. Over this age,insufficient healthy trees are available to form thestand after sanitation. For heavily infected olderstands on productive soils, eady salvage, with removalof all infected understory, is recommended to returnthe land to full production.

In most cases. the sites supporting infected shore pinein the study area are on rocky hilltops and are moresuited to recreation (hiking, nature study) than tocommercial forestry. Even for recreational purposes,however, dwarf mistletoe will have to be consideredan important factor affecting the appearance andgeneral health of the stands.

The particular habitat requirements of shore pine hasisolated a unique gene pool of A. tsugense from thecommon western hemlock host. Inoculation experi·ments by Smith (38) indicate some degree of geneticdifferentiation, although the seed source. unlike thestudy area, was from an area where infected shorepine and infected western hemlock forest standhabitats were adjacent.

8efore a decision can be made on its taxonomicposition, a wider spectrum of host/parasite relation·ships, morphological and physiological characteristicsof the dwarf mistletoe and its historical developmenthas to be studied. Field inoculations of dwarf mistle­toe seed collected from shore pine from the mountaintops onto western hemlock and from hemlock toshore pine, and measurements of quantitativecharacters for morphological differentiation of thetwo races would be helpful in clarifying the taxonomicstatus of A. tsugense on shore pine.

ACKNOWLEDGMENTS

The author expresses his appreciation to Dr. A.8.Smith for his help and encouragement. He also thanksMr. James Case. University of Calgary for the lichenidentifications, Mr. Adolf Geska. University ofVictoria. for verifying or determining some of theplant specimens and Dr. F.G. Hawksworth, U.S.Forest Service, Fort Collins, Colo.. for reviewing apreliminary draft of the manuscript.

REFERENCES

1. Baranyay. J.A. (19681. Squirrel feeding on dwarfmistletoe infections. Bi-Mon. Res. Notes24(5): 41-42.

2. Baranyay, J.A. and A.B. Smith (1972). Dwarfmistletoes in British Columbia and recommen­dations for their control. Can. For. Serv..Pac. For. Res. Centre, BC-X-72. 18 pp.

3. Bird, C.D. and R.D. Bird (1973). Lichens ofSaltspring Island, British Columbia. Syesis6: 57-80.

4. Black, CA (1965). Methods of soil analysis.Part I. Agronomy No.9. Madison, Wisconsin.770 pp.

5. Braun-Blanquet, J. (1965). Plant sociology, thestudy of plant communities (Trans!. rev. anded. by G,o. Fuller and H,S. Conard), Hafner,London. 439 pp.

6. Canadian Soil Survey Committee (1974). Thesystem of soil classification for Canada. Can.Dept. Agrie., Pub!. 1455. Queen's Printer,Ottawa.255 pp.

7. Clapp, C.H. 11917l. Sooke and Duncan Mapareas, Vancouver Island. Geel. Surv., Canada,Mem.96. 445 pp.

8. Day, J.H., L. Farstad and D.G. Laird (1959).Soil survey of southeast Vancouver Islandand Gulf Islands, British Columbia. ReportNo.6 of the British Columbia Soil Survey.Can. Dept. Agric., Research Branch. 104 pp.

9. Forest Club (1971). Forestry handbookfor British Columbia. University of BritishColumbia, Vancouver, B.C. B15 pp.

10. Forward, Charles N (19691. Land use of theVictoria area. B.C. Geographical Paper No.43, Geological Branch, Dept. of Energy,Mines and Resources, Ottawa. 25 pp.

19

14. Hawksworth, Frank G. (1958). Rate of spreadand intensification of dwarf mistletoe inyoung lodgepole pine stands. J. For. 56(6):404·407.

15. Hawskworth, Frank G. (1975). Personal commu­nication.

16. Hawkswonh, Frank G. and Thomas E. Hinds(19641. Effects of dwarfmistletoe on imma­ture lodgepole pine stands in Colorado. J.For. 62111: 27-32.

17. Hawksworth, Frank G. and Arthur A. Lusher(1956). Dwarfmistletoe survey and controlon the Mescalero-Apache Reservation, NewMexico. J. For. 54(6): 384-390.

18. Hawksworth, Frank G. and Delbert Wiens(1972). Biology and classification of dwarfmistletoes IArceuthobium). USDA, Agric.Handbook 401, 234 pp.

19. Hitchcock, C.L., A. Cronquist, M. Ownbey, andJ.w. Thompson 11955·1969). Vascular plantsof the Pacific Northwest. Univ. WashingtonPress. Seattle. 5 VoL

20. Holland, S.S. (1964). Landforms of BritishColumbia. A physiographic outline. BritishColumbia Dept. Mines and PetroleumResources, Bull. No. 4B. Queen's Printer,Victoria, B.C. 138 pp.

21. Kojima, Satoru (1971). Phytogeocoenoses ofthe coastal western hemlock zone in StrathconaProvincial Park, British Columbia, Canada.Ph.D. Thesis, Univ. British Columbia. 322 pp.

22. Krajina, V.J. (1969). Ecology of forest trees inBritish Columbia. Ecol. of Western N. Am.2(1): 1-147.

23. Kuijt, Job (1956). A new record of dwarf mistle­toe on lodgepole and western white pine.Madrono 13(5): 170-172.

12. Funk, A., R.B. Smith and J.A. Baranyay (1973).Canker of dwarf mistletoe swellings onwestern hemlock caused by .fimlli! fuckelianavar. macrospora. Can. J. For. Res. 311}: 71-74.

25. Lawton, Elva (1971). Moss flora of the PacificNorthwest. Nichinan, Miyazaki, Japan. HattoriBot. Lab. 362 pp.

11. Franklin, Jerry F. and C.T. Dyrness (19731.Natural vegetation of Oregon and Washington.USDA Forest Service, General TechnicalReport PNW·B. 417 pp.

24. Kuiit, Job (19631.mistletoes and theirin western Canada.186: 134-148.

Distribution of dwarffungus hyperparasitesNat. Mus. Can. Bull.

13. Hale, M. and W. Culberson (1970). A fourthchecklist of the lichens of the continentalUnited States and Canada. Bryologist 73:499·543.

26. McKee, Bates (1972). Cascadia - the geologicevolution of the Pacific Northwest. McGraw­Hill Inc. U.S.A. 394 pp.

27. McMullan, E.E. (1971). Methods of analysis,soils· biochemistry laboratory service. Can.Dept. Fish. For. Inform. Rept. BC·X·50.49 pp.

28. Muir, John A. (1973). CylindrocarDOn Jli1l.ll, anew combination for Septoqloeum gillii ondwarf mIstletoe. Can. J. Bot. 51(10): 1997·1998.

29. Munsell Soil Color Charts (1954). Munsell ColorCompany Inc., Baltimore, Maryland.

30. Orloci, laszlo (1964). Vegetational and environ·mental variations in the ecosystems of theCoastal Western Hemlock Zone. Ph.D. Thesis.Univ. British Columbia. 204 pp.

31. OttO, G.F. (1968). lichens of British Columbia.I. Species not previously recorded from theprovince. Bryologist 71: 368-369.

32. Ono, G.F. and T. Ahtl (1961). lichens of BritishColumbia: Preliminary checklist. Dept. Botany,Un;v. British Columbia. 40 pp.

33. Packee. Edmond C. (1972). The biogeochmaticwbzones of Vancouver Island and the adjacentmainland and islands. MacMillan Bloedellimited, Forestry Division, For. Res. Note 1.6 pp.

20

34. Peden, D.G. (19671. Vegetation and ecology ofRithet's Bog, Royal Oak, British Columbia.B. Sc. (Honours) Thesis, Univ. Victoria,unpublished.

35. Rigg, George B. (19221. A bog forest. Ecology3(2): 201-213.

36. Roemer, Hans L. (19721. Forest vegetation andenvironments on the Saanich Peninsula,Vancouver Island. Ph.D, Thesis, Univ, Victoria.405 PP.

37. Schofield, W.B. (196B). A selectively annotatedchecklist of British Columbia mosses. Syesis1: 163-175.

38. Smith, R.B. (1914). Personal communication.

39. Smith, R.B. (1974). Infection and developmentof dwarf mistletoes on plantatIon-growntrees in British Columbia. Can. For. Serv.,Pacif. For. Res. Centre, Inform. Rep. BeX-97.21 pp.

40. Smith, R.B. and E.F. Wass (1976). Field evalua­tion of ecological differentiation of dwarfmistletoes on shore pine and western hemlock.Can. J. For. Res. lin press).

41. Taylor, T.M.C. (l966). Vascular flora of BritishColumbia. Preliminary checklist. Dept. Botany,Univ. British Columbia. 31 PP.

21

APPENDICES

AP

PE

ND

IXl.

Bas

icp

lot

dat

a

Lo

cati

on

Plo

tA

spec

tS

lop

eP

osi

tion

Lan

dty

pe

Hyg

roto

pe

00

.10

11%

10

0cl

ass

l:!IA

BC

DE

FR

elie

fsl

ope

{Tre

esl

{Sh

rub

s!(H

erb

sl(B

ryo

ph

ytes

)(L

ich

ens)

{Bar

eR

ock

}

Mt.

Hel

mck

en1

316

7T

op

R.O

.C..!

!!0

7565

2585

81

Str

aig

ht

Mt.

Wel

ls2

336

17U

pp

erC

ollu

vial

095

305

100

10

Co

nca

vesl

ope

Mt.

Wel

ls3

4014

To

pC

ollu

vial

·19C

305

100

10

Str

aig

ht

slop

e

Mt.

Man

uel

431

234

Mid

dle

Co

lluvi

al·1

7040

3'

801

0S

trai

gh

tto

GU

lmp

ersl

ope

conc

ave

Rag

ged

Mtn

.5

270

1T

op

R.O

.C.

·185

8010

451

0S

ligh

tly

conc

ave

Gli

nz

Cre

ek6

9C40

Lo

wer

Ter

race

+265

7530

50

0C

on

cave

Hill

22

713

510

To

pR

.O.C

.·3

6550

1080

152

Str

aig

ht

and

rock

kno

lls~

Mt.

Mat

hes

on

810

13U

pp

erR

.O.C

.·2

9810

1295

50

Str

aig

ht

~

Blu

ffM

tn.

924

915

Up

per

R.O

.C.

·275

555

955

1C

onca

vean

dco

nve

x(r

ock

kno

lls)

Mt.

Wo

rk10

204

15T

op

R.O

.C.

·245

2530

9C,

5S

trai

gh

tan

dco

nvel

t(r

ock

!

Mt.

Jack

1128

010

To

pR

.O.C

.·2

7530

485

52

Str

aig

ht

MI.

Mag

uir

e12

325

15U

pp

erR

.O.C

.·1

9575

295

11

Con

cave

ind

epre

ssio

n,

con

vex

onro

ck

Kir

by

Hil

l13

4220

To

pR

.O.C

.·1

5025

170

42

Str

aig

ht

Isal

all

and

con

vex

{ro

ck!

.;R

.O.C

.·R

ock

ou

tcro

p

01H

ygro

top

ecl

ass

fro

mO

rlo

ci(3

D).

o(M

eSIc

),m

ediu

mte

xtu

red

dee

pso

ils,

wit

ho

ut

seep

age

·3(V

ery

dry

),kn

olls

and

peak

so

fro

cko

utc

rop

s+1

(Mo

ist)

,de

epso

ils,

tem

po

rary

seep

age

-2(D

ry).

Lit

hic

soils

+2

(Wet

),p

erm

anen

tse

epag

ecl

ose

toth

eso

ilsu

rfac

e

·1(M

od

erat

ely

dry

l,sh

allo

wco

arse

sto

ney

glac

ial

tills

+3

(Sw

amp

y).

spri

ng

-wat

ersw

amps

,m

uske

gsan

dst

ream

-ed

ge

hab

itat

s

23

APPENDIX II. Representative soil profile descriptions

Plot 1 - Degraded Dystric BrunilOl

Horizon Depth lcm)

L 2-1

F-H '-0A,]} 0'

Bmce, 1·10

Bmcc2 10-42

BC 42·61

BCg 61-85

Bedrock B5+

Description

Undecomposed conifer needles and salalleal/es

Friable duff mull like

Trace

Reddish brown (5.0 YR4/41 moist, dark brown 17.5 YR4/4)dry, gravelly loam, pH 5.2, large roots I> 10 mm) abundant

Reddish brown (5.0 YR4/4) moist, dark brown (7.5 YA4/41dry. gravelly sandy loam, pH 5.1

Brown (10 YR 4/3) moist, pale brown (10 VAG/3) dry.gravelly sandy loam, pH 4.7

Mottled brownish yellow 110 YR 618) and pale red (2.5y 6 f21 mOiSt, gravelly sandy clay loam. pH 4.7

1/ Ae was 7 em thick in soil Sa

Plot 8 - Orthic Dynric Brunilol

Horizon

L

F-H

Bm,

BC

IIC

Bedrock

Depth (em)

7-'4-0

07

7·17

17·28

28-50

50·67

67·69

69+

Duc:ription

Undecomposed conifer needles

Very friable. duff mull like, containing high charcoal content

Dark vellowish brown (10 YA3/41 moist, brown to darkbrown (7.5 YR3/41 dry, gravelly loam to sandy loam, pH 5.5

Brown to dark brown (7.5 YR4/4) moist. brown 17.5 YA5/4)dry, gravelly loam, pH 5.4

Dark yelloWish brown (10 YR4/41 moist, yellowish brown(10 YR5/41 dry, gravelly sandy loam. pH 5.5

Olive brown (2.5 y4/4J moist, light yellowish brown (2.5y6/41 dry, very gravelly sandy loam, pH 5.0

Olive brown (2.5 y4/41 moist, light vellowish brown (2.5Y6141 dry, very gravelly sandy loam·loamy sand, pH 4.7

Root layer contact with bedrock

Plot 7 . lithic Dynric Brunitol

Horizon

L

'-H

Ah

Bm,

BC

Bedrock

Depth (cml

4-2

2-0

0-'

'-7

7·19

43'

Description

Undecomposed moss material

Very friable mull

Trace

Dark yellowish brown flO YR3/4l motst. brown todark brown (7.5 YR4/41 dry. gravelly loam. pH 5.3

Dark reddish brown 15 YR3/41 moist. brown to darkbrown t7.5 YA4/4) dry. gravelly loam. pH 5.3

Dark reddish brown 15 YR3/4) moist. dark yellowishbrown (10 YR4/4) dry. very gravelly sandy loam.pH 5.0

Dark yellowish brown (10 YA4/41 moist. yellowishbrown (to YA5/41 dry, very gravelly sandy loampH 5.0

Plot 6 • Drthic Sombric Brunisols

Horizon

L

'-H

Ah

BC

Bmb

C,

C2

Depth (em)

3-'1.()

O-g

9-32

32·49

49·66

66·81

81·103+

Description

Undecomposed needles and sword fern fronds

Friable mull

Dark brown (7.5 YR3/2) moist. dark yellowish brown(10 YA4/41 dry, gravelly sandy loam, pH 5.4,charcoalpresent, earthworms

Dark yellowish brown (10 YA3/4) moist, darkyellowish brown (10 YR4/4) dry. very gravellysandy loam. pH 5.5

Dark yellowish brown (10 YA4/4l moist, lightyellowish brown (2.5 YR6/4) dry. very gravellysandy loam. pH 5.7

Dark yellowish brown (10 YR4/41 moist, yellowbrown (10 YA5/4) dry, gravelly sandy loam. pH 5.7

Olive brown (2.5 y4/4) moist, light yellow brown(2.5 y6/41 dry, some mottling, gravelly sandy loamto loamy sand, pH 5.8

Olive brown (2.5 y4/4) moist. light yellow brown(2.5 y6/4l dry, gravelly loamy sand, pH 5.8

Plot 4• . lithic Sombtic Brunisol

Horizon Depth (em)

L 4-2

F-H 2'()

Ah 0-6

8m 6·15

Bedrock 15+

25

Deu:ription

Undecomposed dead moss and pine needles

Fibrous mor

Dark reddish brown (5 YR 2 /2) moist, dark brown(10 VR3/3) dry, very gravelly loamy sand, pH 4.9

Dark brown (10 VA3;3) moist, brown to dark brown(10 YR4/31 dry. gravelly loam, pH 4.6

AP

PE

ND

IXII

I.S

peci

esan

dco

vera

gefo

rin

tens

ive

plo

ts.

PIO

Ino

,R

ock

ykn

oll

on

ly

Spe

cies

by

stra

tum

,2

34

57

BB

'011

'2'3

I9

,10

,1

1,

'2,

'3,

TR

EE

ST

RA

TU

M

T,

(>1

8m

)

Pse

udot

suga

men

zies

ii2

2+

32

Pin

usco

nto

rta

var.

con

tort

a+

T2

(9m

·18

m)

Pin

usco

nto

rta

var.

con

tort

a,

42

43

33

,4

22

Pse

udot

suga

men

zies

ii,

22

22

,3

,T

3(4

.5m

-9m

l

Pin

usco

nto

rta

var.

con

tort

a3

,,

,2

,2

+,

43

Pse

udot

suga

men

zies

ii,

++

,,

++

,2

I~

Arb

utu

sm

enzi

esii

++

,0

-

T4

«4

.5m

)

Pin

usco

nto

rta

var.

con

tort

a4

2+

+,

,,

2+

42

I+

Pse

udot

suga

men

zles

ii+

++

++

,+

,,

,,

+

Arb

utu

sm

enzi

esli

,3

•,

Sal

ixsc

oule

riana

+,

++

+•

•,

+

Th

uja

plic

ata

,+

Tsu

gah

ete

rop

hyl

la•

Aln

us

rubr

a,

SH

RU

BS

TR

AT

UM

Ga

ulth

eri

ash

allo

n3

,,

,3

2,

34

53

+,

+

Ber

beris

nerv

osa

,,

,+

,+

,,

+,

+

Arc

tost

ap

hyl

os

colu

mb

ian

a,

32

+3

+,

,+

+

Arc

tost

ap

hyl

os

uva·

ursi

,+

++

++

12

1+

+

Ros

agy

mnO

Cllr

pa1

++

1+

+1

++

+,

+

Ho

lod

iscu

sd

isco

lor

+,

+2

++

++

+

AP

PE

ND

IXIl

LS

peci

esan

dco

vera

gelo

rin

tens

ive

plot

s.(C

on

tinu

ed

)

Plo

tno

.R

ock

ykn

oll

on

lyS

peci

esb

yst

ratu

m1

23

45

7B

910

1112

13I

9,

10,

11

,1

2,

130

Pa

chys

tima

myr

sin

ites

++

++

++

Rub

usur

sinu

s+

++

++

I+

Am

ela

nch

ier

aln

ifo

lia+

++

Sat

urej

ad

ou

gla

sii

++

+S

ymp

ho

rica

rpo

sal

bus

++

Cyt

isu

ssc

opar

ius

+3

Va

ccin

ium

ova

tum

11

I+

Va

ccin

ium

pa

lVif

oliu

m+

+Ju

nip

eru

sco

mm

un

isLi

nnae

ab

ore

alis

HE

RB

ST

RA

TU

M

Go

od

yera

ob

lon

gifo

Jia

I~

++

++

1+

+1

++

+~

Tri

en

talis

lati

folia

+1

++

+1

++

Sel

agin

eJla

wal

lace

i+

++

+2

Ery

thro

niu

mor

egan

um+

++

+,

++

Hie

raci

um

alb

iflo

rum

++

++

++

+I

+H

aben

aria

unal

asce

nsis

,1

1+

+L

iste

raco

rda

ta+

+1

++

I+

Circ

aea

alp

ina

++

++

,E

lym

u$

glau

cus

+2

3+

2I

+D

ocle

cath

eon

hend

erso

nii

+1

11

1M

on

tia

pe

rlo

liata

++

1+

Fra

garia

sp.

++

++

Fes

tuca

rub

ra2

+3

+1

+A

ira

prae

cox

2+

+4

1I

++

Co

llin

sia

pa

lVifi

ora

++

++

San

icul

acr

assi

caul

is+

1+

++

Heu

cher

am

icra

nth

a+

++

++

Cam

assi

aq

ua

mas

h+

Ach

ille

am

ille

loliu

m+

++

I+

++

AP

PE

ND

IX11

1.S

peci

esan

dco

vera

gefo

rin

tens

ive

plo

ts.

(Co

ntin

ue

d)

Pto

tno

.R

ock

ykn

oll

on

lyS

peci

esb

yst

ratu

m1

23

45

7B

910

1112

13I

9,

'0,

11

,'2

,'3

;0

Po

lyst

ich

um

lon

chlt

is+

++

Fes

tuca

occ

ide

nta

lis

+,

,I

++

Cal

ypso

bulb

osa

++

Hab

enar

iao

rbic

ula

ta+

+C

ora

llorh

iza

mac

ulat

a+

+P

lect

ritls

cong

esta

++

Sed

umst

en

op

eta

lum

++

+R

umex

acet

osel

la+

+I

+P

oly

stlc

hu

mm

un

itu

m+

+A

nth

oxa

nth

um

od

ora

tum

+,

3L

om

ati

um

utr

icu

latu

m+

Mad

iam

ad

ioid

es

+H

ypO

chae

risra

dic

ala

+A

lliu

mce

rnu

um

+I

~

Zyg

aden

usve

nosu

s+

'"L

iliu

mco

lum

bia

nu

m,

Fra

garia

vese

aI

+F

raga

riach

iloen

sis

++

Sed

umsp

ath

ulif

oliu

mI

+E

rlo

ph

yl1

um

lan

atu

mO

smo

rhiz

apu

rpur

ea+

Bos

ehni

akia

ho

oke

riP

oly

po

diu

mhe

sper

ium

++

+C

ryp

tog

ram

ma

cris

pa+

I,

+A

irs

cary

op

hyl

la+

LU

lula

mu

ltif

lora

++

Fes

tuca

sub

ulif

lora

+A

gros

tissp

.+

Car

el(

ino

ps

+F

estu

cab

rom

oid

es+

An

ten

na

ria

sp.

+V

iola

glab

ella

+L

acl

uca

bien

nis

+C

arex

rosH

AP

PE

ND

IX11

1.S

peci

esan

dco

vera

gefo

rin

tenS

ive

plot

s.(C

on

tinu

ed

)

Plo

tno

.R

ock

ykn

oll

on

lyS

peci

esb

yst

ratu

m1

23

45

78

910

1112

139a

lOa

lla

12a

13a

Car

expe

nsyl

vani

ca•

Ap

ocy

nu

ma

nd

rosa

em

ifoliu

m•

Pyro

l.d

en

tala

BR

YO

PH

YT

E&

LIC

HE

NS

TR

AT

UM

Eu

rhyn

chiu

mor

egan

um4

31

34

45

2•

•3

Rh

ytid

iad

elp

hu

str

iqu

etr

us

22

43

11

••

•P

eltlg

era

apht

hosa

1•

•1

12

••

•D

icra

nu

mh

ow

cllii

2•

••

1+

+P

oly

tric

hu

mju

nip

eri

nu

m1

++

++

+I

32

33

2H

yto

com

ium

sple

nden

s1

13

11

++

Po

lytr

ich

um

pili

leru

m1

++

+2

++

I•

Iso

the

ciu

mcr

ista

tum

++

1+

Rh

aco

mit

riu

mca

nesc

ens

22

++

•I1

3•

Dlc

ran

lum

sco

pa

rlu

m2

+2

2~ '"

Sca

pani

ab

ola

nd

eri

++

++

lso

the

ciu

mst

olo

nif

eru

m1

1+

+P

eltlg

era

cant

na1

++

+

I+

Cla

donl

alu

rca

ta+

+•

+S

phae

roph

orus

glob

osus

++

+•

Rh

ylic

liad

etp

hu

slo

reus

++

Dic

ran

um

lusc

esce

ns+

++

I3

22

2+

An

titr

ich

lacu

nip

en

du

ta+

+G

rim

mia

tric

ho

ph

ylla

++

Ho

ma

loth

ecl

um

pm

na

tifi

clu

m+

+R

ha

com

ltrl

um

lanu

gino

sum

+2

I+

22

Cla

do

nia

be

ltid

iflo

ra+

++

+H

om

alo

the

ciu

mm

eg

ap

tilu

m+

Leuc

olep

ism

enzi

esii

+B

ryu

mca

pilla

re+

Po

lytr

ich

um

com

mu

ne

Por

ella

navl

cula

rls

+P

ohtia

nuta

ns+

Rh

aco

mllr

ium

he

tero

stic

hu

m

Mn

ium

sptn

ulos

um+

AP

PE

ND

IXII

I.S

peci

esan

dco

vera

gelo

rin

tenS

IVe

Illo

u.

(Co

ntl

nu

ed

l

Plo

tno

.R

ock

ykn

oll

on

lyS

peci

esb

yst

ratu

m,

23

45

7B

910

II'2

13I

9,

10

,ll,

12

,'3

0

Hyp

nu

mci

rcin

ale

•H

ypn

um

subi

mpo

nens

•R

hyt

ldlo

psi

sro

bust

a2

Par

mel

lasa

xatil

is•

I+

Par

mel

iasu

lcat

a+

+P

arm

elia

omph

alod

es+

Par

meh

ata

ract

ica

+C

orm

cula

rla

acul

eata

++

Th

am

no

liave

rmic

ular

is+

Cla

doni

ap

yxid

ata

,•

+S

tero

cao

lon

tom

en

tosu

m+

+2

++

+U

mb

ilica

ria

hir

suta

V+

+C

lado

nia

un

cia

lis+

wC

lad

on

iaco

ccife

ra+

+a

Cla

do

nia

no

rrlin

i?•

Cla

do

nia

sp.

+C

lad

on

iaco

rnu

ta+

+P

lag

ioth

eci

um

un

du

latu

m+

Cla

do

nia

ran

gife

rin

a+

Um

bili

cari

ave

llea

+H

ypa

gym

nia

phys

odes

+C

lad

on

iach

loro

phae

a+

•C

lad

on

iagr

acili

sva

r.d

ilata

ta+

JJ1L

ich

en

pre

vio

usl

yfo

un

do

nly

once

inB

riti

shC

olu

mb

iaby

Bir

dan

dB

in.I

(31

onS

alts

prin

gIs

land

.

1)e

ove

r·ab

unda

nce

scal

e5

(7&

100%

).4

(51

·75

%).

3(2

&5

0%

).2{

&25

%1.

1(1·

5%1.

+(le

ssth

an

1%).

r(s

olit

ary

indi

Vid

ual

With

sma

llco

ver)

.

2)N

om

en

cla

ture

and

au

tho

nti

es

for

the

vasc

ular

plan

tsfo

llow

Hit

chco

cket

al.

(19)

,L

aw

ton

(251

for

mos

ses

and

Hal

ean

dC

ulb

ert

son

(13

)lO

tlic

hens

.A

nu

mb

er

of

chec

klis

tsw

ere

used

tod

ete

rmin

ew

he

the

rp

lan

tsp

ecim

ens

wer

ene

wto

the

pro

vin

cef3

,31

,32

,37

,41

1.

31

APPENDIX IV Some lichens found on shore pine

AleClorla sarmentosa

Cladonia pllVrea

Cladonia theiophila

Hypogvmn1a enteromorpha

Hypogymnia physodes

lecldea sp.

Mycoblastus sangulnanu5

Ochrolechia oregonensis

Ochrolechia upsaliensis

Pertusaria sp.

Platlsmatia glauca

Sphaerophorus globosus

Usnea dasyjX)9a

32

APPENDIX V. location, elevation and size of infested area for individual points surveyed(numbers match survey points on Fig. 11).

No. Location Elevation Size of Infested1m) Area (ha)

Mt. Helmcken 305 '3

2&3 Mt. Wells 335 2

4 Ml Manuel Quimper 536 2

5 Ragged Mtn. 57. 12

6 Glinz Creek 244 < 0.5

7 Hill 22 335 3

8 Mt. Matheson 274

• Bluff Mtn. 54. 165

10 Mt. Work 427 32

11 Mt. Jack 646 •12 Mt. Maguire 244 Healthy

13 Kirby Hill 457 13

14 MI. Braden 467 2

15 Hill 26 518 6

16 Mt. McDonald 42.

17 Hill 36 610 23

18 Empress Mtn. 673 -:: 0.5I. Memory Island 116 -:0.5

20 Waterloo Mtn. 1055 Healthy

21 Redflag Mtn. 305 Healthy

22 Mt. Bhnkhorn 244 Healthy

23 % mile N.W. of Boneyard Lake 427 0.5

24 Jocelyn Hill 396 15

25 Mt. Jeffrey 57. Healthy

26 Bamberton Provo Park 15 0.5

27 Iron Mine Hill 31 35

28 Mt. Healy 722 24

29 West side of Soake lake 186 •30 Mt. Finlayson 40. 0.5

31 Trap Mm. 711 17

32 Mt. Newton 244 Healthy

33 Area "8" Muir Ck. 76 Healthy