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Acknowledgements

William M. Ciesla, Forest Health Management International, Fort Collins, Colo., and

Aerial Survey Coordinator, Colorado State Forest Service (CSFS), is the primary author ofthe 2009 Report on the Health of Colorados Forests.

Tanks to the following Colorado State Forest Service employees who served on the ReportWorking Group and/or provided information, guidance and feedback.

Chuck Dennis, Special Projects Forester, Broomeld, Colo.

Joe Duda, Forest Management Division Supervisor, Fort Collins, Colo.

Jan Hackett, Policy and Legislative Aairs Specialist, Denver, Colo.

Meg Halord, Assistant District Forester, Franktown District, Franktown, Colo.

Ben Pohl, Assistant District Forester, Boulder District, Longmont, Colo.

im Reader, Utilization and Marketing Forester, Durango District, Durango, Colo.

Kelly Rogers, District Forester, Grand Junction District, Grand Junction, Colo.

Dr. S. Sky Stephens, Entomologist, Fort Collins, Colo.

Tanks to those who reviewed and/or provided information for this report:

Dr. Donald Bright, C. P. Gillette Museum o Arthropod Biodiversity,Department o Bioagricultural Sciences and Pest Management, Colorado State University,Fort Collins, Colo.

Robert Cain, Entomologist, USDA Forest Service, Lakewood, Colo.

Dr. ony Cheng, Director, Colorado Forest Restoration Institute, Warner College o NaturalResources, Colorado State University, Fort Collins, Colo.

Patricia M. Ciesla, Forest Health Management International, Fort Collins, Colo.

Brian Howell, Aerial Survey Program Manager, USDA Forest Service, Lakewood, Colo.

Dr. Brian Kent, Research Forester, Human Uses, Economics, and Decision Sciences,Rocky Mountain Research Station, USDA Forest Service, Fort Collins, Colo.

Dave Leatherman, Entomologist, CSFS (retired), Fort Collins, Colo.Joseph Lohnes, City Forester, Greeley, Colo.

Jeannie Nicholson, Gilpin County Commissioner, Central City, Colo.

Jennier Ross, GIS Specialist, USDA Forest Service, Monument, Colo.

Irene Shonle, Director, Colorado State University Extension, Gilpin County, Black Hawk, Colo.

Kyle Sylvester, City Forester, Brighton, Colo.

Dr. David R. Smith, Systematic Entomology Laboratory, National Museum o Natural History,Smithsonian Institution, Washington, D.C.

Dr. Ned isserat, Proessor o Plant Pathology, Colorado State University, Fort Collins, Colo.

Dr. Jim Worrel, Forest Pathologist, USDA Forest Service, Gunnison, Colo.

Ralph Zenz, City Forester, Fort Collins, Colo.

Special thanks to: Katherine imm, Outreach Division Supervisor, Judy Serby, ConservationEducation Program Manager, CSFS, or project leadership. Tanks also to Lisa Mason,Outreach Forester, CSFS, or GIS support. Brad Tomas, Graphic Communications Specialist,Communications and Creative Services, Colorado State University, or graphic design, layout,and production. Barbara Dennis, Publications Coordinator, Communications and CreativeServices, Colorado State University, or project management.

Cover Photo: Ingrid Aguayo. All other photos by Bill Ciesla unless otherwise noted.


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January 2010

Te 2009 Report on the Health o Colorados Forests: Treats to Current and FutureForest Resources provides an overview o insect and disease conditions in all o thestates orests. It also includes sections on urban orests, pion-juniper woodlands,aspen orests and urban orests. In addition, this report introduces the StatewideForest Resource Assessment, a new initiative mandated by an amendment tothe Federal Cooperative Forestry Assistance Act. Interactions between orests,wildre, insects, diseases and humans also are reviewed, as is the role orests play inprotecting Colorados watersheds.

This report is the ninth in a series developed by the Colorado State Forest Service(CSFS) on the condition o Colorados orests. Much o the inormation contained in

this report is derived rom the annual orest health aerial survey, a cooperative projectbetween the CSFS and the Rocky Mountain Region o the USDA Forest Service

(USFS) that covers all land ownerships. In addition, the 17 CSFS district ocesconduct orest insect and disease assessments and provide technical assistance to

private orest landowners. These activities supplement the inormation in this report.The CSFS, in conjunction with cooperators and stakeholders, is working to

minimize the ecological, social and economic impacts o these events, primarilythrough long-term orest management such as thinning, prescribed burning andtimely harvesting o mature orests. These activities are designed to maintain the vigor

and health o all o Colorados orests.I hope you will nd the inormation contained in this report to be inormative

and helpul. I invite you to contact your nearest CSFS oce to learn more about ourorests and what you, as a citizen/landowner, can do to help manage and protect this

valuable resource.

Tank you or your interest in Colorados orests.

Je JahnkeState Forester and Director

Colorado State Forest Service


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Te purpose o the annual oresthealth report is to provide a credible,

scientically sound basis rom which toengage in public dialogue regarding theuture o Colorados orests. It is in thispublic arena that the needs and valueso Colorados orests will be evaluatedso decisions can be made regardinguture management and investment oresources. Each annual orest healthreport investigates critical orest healthissues, including the identication opriority areas across the state wherecurrent orest conditions demand timelyaction. Te inormation contained inthis report builds on the oundationlaid in previous reports by updatingreaders on issues o current concern andproviding additional details or publicdialogue. Coloradans can use thesedocuments to better understand howthe interactions between natural andhuman orces shape our orests and howinormed citizens can contribute to thedecisions made regarding uture orestmanagement. o view past issues o theannual orest health report, visit http://

css.colostate.edu/pages/pub-css2.html .It is important to note that while this

years report provides a broad overviewo the numerous insect and disease issues

challenging our state, the mountainpine beetle epidemic continues to be the

predominant issue due to the threats itpresents to human saety, communities,

critical inrastructure, recreation andtourism, wildlie habitat, watersheds andwater supplies, and Colorados economy.

We anticipate that the impacts o theMPB epidemic will be our primary

ocus or the next several years, andwe will continue to engage in public

dialogue to determine how to mosteectively mitigate its impacts and createa uture orest that is more resilient to

catastrophic insect and disease epidemics.MPB inestations encompassed

1.02 million acres o the states 1.5million areas o lodgepole pine orests.

Inestations continued to intensiyalong portions o the Front Range andas ar south as Fairplay. Lodgepole

Executive Summaryorests west o the Continental Divide

have suered heavy losses rom MPB

since 1998, and the outbreak has run itscourse in many areas because most o

the susceptible trees have been killed.Evidence suggests that inestations are

building in ponderosa pine orests alongthe Front Range. Increased attacks were

seen in ponderosa pines where ponderosaand lodgeole pine orests adjoin. Inearly 2009, an outbreak was detected

in ponderosa pine orests located innorthern Larimer County near the

Wyoming border.Spruce beetle inestations continued

in high-elevation Engelmann spruceorests in several areas o the state, witha total area o 114,000 acres o active

inestations detected in 2009. Treemortality caused by a combination o

western balsam bark beetle and rootdisease-causing ungi continued in

many high-elevation orests, but at asignicantly reduced rate rom past

years. Localized inestations o Douglas-

r beetle occurred in portions o theRampart Range between Denver and

Colorado Springs, and in several otherareas o the state.

In 2009, western spruce budwormdeoliation o Douglas-r, white r

and Engelmann spruce increased andintensied to a total o 382,000 acres.Deoliated areas included portions o the

Culebra, Flat Top, Sangre de Cristo, SanJuan and Rampart ranges.

Special surveys again were conductedor early detection o gypsy moth

and emerald ash borer, both exoticpests. Three male gypsy moths were

trapped in two locations in Coloradoin 2009. Additional cases o thousandcankers disease o black walnut, which

is caused by multiple ungi spread bythe walnut twig beetle, a native insect

that has recently expanded its range,were detected in several Coloradocommunities.

Aspen decline continues to be aconcern, especially at the lower-elevation

limits o its natural range. However,ater two seasons o normal or above

normal moisture, there are indicationsthat the rate o aspen decline has at least

stabilized and may be decreasing. In2009, 342,000 acres o aspen decline and

mortality were mapped, compared to542,000 acres in 2008.

Although insect and disease outbreaksare normal and contribute to thedynamics o Colorados orests, they can

aect scenic values, alter water quality

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2009 Forest Health Report

Executive Summary


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In response to an amendment to theFederal Cooperative Forestry AssistanceAct o 1978 (CFAA), enacted as parto the 2008 Farm Bill, Colorado hasembarked on a statewide assessment oits orest resources. Tis assessment willguide the development o a long-termorest resource strategy or Colorado.Te purpose o the assessment andstrategy is to ensure that ederal andstate resources are ocused on important

landscape areas those that provide thegreatest opportunities to address sharedmanagement priorities and achievemeasurable benets.

Colorados Statewide Forest ResourceAssessment identies important orestlandscapes across the states nearly 19

million acres o orests and woodlandsaccording to three national themes:

Conserving working orest landscapes

Protecting orests rom harm

Enhancing public benets rom treesand orests

The Colorado State Forest Service(CSFS) is leading the assessment,

with signicant assistance rom TheNature Conservancy, in partnershipwith representatives o other land

Pion - Juniper

Aspen

Ponderosa pine

Spruce - Fir

Douglas-r

Lodgepole pine

Mixed orest types

Forested riparian

28%

12%

8%

17%4%8%

21%

1%

Colorados Forest

Resource Assessment

Above: A orest vista rom the summit o Mt. Margaret, Larimer County.

management agencies and stakeholders

including indigenous tribes, USFS,State Forest Stewardship Coordinating

Committee, State Technical Committeeo the Natural Resources Conservation

Service and the State Wildlie

Committee. All orested lands, regardless

o ownership, are included in theassessment.

The overall approach to theassessment is to develop a series o

thematic maps based on spatial data rom

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Wildlie HabitatAreas that provide critical habitat orboth economically important andimperiled species are identied.

Recreation OpportunitiesForest lands are scored by their abilityto provide opportunities or biking,camping, shing, hiking, hunting,skiing, snow shoeing and water sports.

The Colorado Statewide ForestResource Assessment was initiated inJune 2008 and completed in December

2009. The next phase is development oa strategy on how to address treatment

o the high-priority landscapes identiedin the assessment. This is being

accomplished via a series o discussionsessions in several locations acrossColorado to solicit public input. The

Colorado Forest Restoration Institute isacilitating the sessions. The institute is

based at Colorado State University andwas chartered in response to the Federal

Southwestern Forest Health and WildrePrevention Act o 2004. The objective

o the institute is to help restore thehealth o Colorados orests and reducecatastrophic wildres by providing

orest landowners with the best availablescience in orest ecology, restoration and

management. The statewide assessmentwill culminate with the development

and implementation o the strategy. The

a variety o sources using a geographic

inormation system (GIS). These include:

Conserving WorkingForest Landscapes

Forest Legacy AreasPrivate lands are identied that couldbe set aside to protect environmentallysensitive orests as authorized by a 1990Farm Bill amendment to the CooperativeForestry Assistance Act o 1978.

Spatial Analysis ProjectIdenties non-ederal land withhigh stewardship potential.

Change in Degree o Human ModifcationIdenties lands with a high susceptibilityto undergo modication.

Protecting Forestsrom Harm

Wildfre Susceptibility and Intensity

Data on vegetation type and uelconditions are combined withtopographic inormation to identiythe probability o wildre occurrenceand the amount o resource damagea wildre can cause. Tese data willbe used to identiy priority areas orwildre protection.

Insect and Disease Mitigation PotentialCumulative tree mortality caused byinsects and disease between 2004 and2008 based on annual orest health aerial

surveys and stand basal area rom theForest Inventory and Analysis (FIA)are combined to identiy areas withrelatively low cumulative tree mortalitybut high potential or uture damage.

Enhancing Public Benetsrom Trees and Forests

Critical Watersheds or Drinking WaterData on soil types, slope, existence o

water diversions and re susceptibilityare combined to identiy areas at highrisk o events that could threaten theavailability and quality o domesticwater supplies.

Wildland-Urban Interace ZonesHousing density data are used to denecommunity edges, identiy areas whereorest management is needed to reducewildre risk, and develop evacuationplans in the event o wildre.

Let: Bighorn ram, Big Thompson Canyon.

Below: Fritillary butterfies on thistle. Bottom:

Cones o Douglas-r, Pseudotsuga menziesii.

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strategy will describe how Colorado

proposes to invest both competitive andnon-competitive ederal unding, alongwith other available resources, to address

national and regional priorities, as well

as those identied in the assessment.Forest management programs will beurther rened and ocused to address

the management o Colorados valuableand diverse orest resources, and providetangible benets to all Coloradans.

Right: Logs harvested rom areas damaged

by mountain pine beetle will be processed

into a variety o wood products. Photo: Dan

Bihn.Below: A hiker takes in a mountain vista.

Bottom: Biking is a popular recreation activityin Colorados orests. Photo: Pat Ciesla.

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Colorado ForestInsect and Disease UpdateTis section highlights the status oimportant insect and disease pests inColorados orests. Data were derivedrom several sources, includingthe Colorado orest health aerialsurvey, which is conducted through apartnership between the USFS and theCSFS. In 2009, more than 90 percent oColorados orests (exclusive o pion-

juniper woodlands) were surveyed overthe course o more than 300 hours ina high-wing aircra. Maps that showthe location o pest outbreaks can beaccessed on the web at www.s.ed.us/r2/resources/m/aerialsurvey/. Inaddition, personnel in the 17 CSFSdistrict oces conduct evaluations oorest pest activity on a regular basis andprovide advice to orest landowners onhow to reduce losses. Te inormationthey collect is included in this report.

o North Park, the northern RawahRange in northwestern Larimer Countyand Berthoud Pass, many susceptiblelodgepole pines have been killed andinestations also are declining. Mostareas in which the MPB outbreak hasrun its course still have young lodgepolepine stands. Tese stands are less

Bark Beetles

Mountain Pine Beetle(Dendroctonus ponderosae)

In 2009, MPB continued to be thedominant orest pest in Colorado. Activeinestations continued on 1.02 millionacres o the states 1.5 million acres

o lodgepole/limber pine orests. Teintensity o inestations again increasedin orests east o the Continental Divide,with many stands suering attack rateso at least 10 trees per acre. Inestationsin portions o Grand and Summitcounties, where the outbreak beganduring the late 1990s, have declined dueto the death o the most susceptible trees(those over age 60 with diameters o atleast 6 inches). In some areas east o theContinental Divide, such as portions

Top: Mountain pine beetle outbreaks now

cover vast areas o Colorados landscape.

Above: Mountain pine beetle adult.

Insect & Disease
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susceptible to attack, although sometrees have died. Young, small-diameterlodgepole pines are too small to producelarge numbers o next-generationbeetles. In addition, a ew larger trees

also have survived the outbreak.An interesting aspect o MPB

inestations in 2009 is that the oliageo trees attacked in 2008 did not adeto their typical red-orange color until

late summer. Throughout most o thesummer, many lodgepole pines dying

rom MPB attack were a sickly yellowcolor, which made aerial detection

o trees attacked in 2008 morechallenging. This phenomenon wasprobably due to the cool, wet summer

o 2009, which delayed ading.

In some areas o Colorado, lodgepole

pines were attacked by three species obark beetles. In addition to MPB, thepine engraver (Ips pini) killed primarily

small-diameter trees o 5 inches or less.

High levels o engraver beetle activitywere detected rom Meeker Park southto Central City, and in portions o

Larimer, Boulder and Gilpin counties.A third species, identied as Pityogenesplagiatus knechteli, also attacked

lodgepole pines. This insect is considereda common secondary invader o

lodgepole pines but was seen attackingtrees in large numbers at numerous

locations. In a ew cases, all three barkbeetles were invading the same trees.

Many people are concerned thatthe current outbreak in lodgepole pine

will spread to ponderosa pine orests,

especially along the Front Range whereMPB historically has been a pest inponderosa pine orests. Evidence suggests

that the potential is high or an MPB

outbreak in ponderosa pine as beetlesmove into orests in which ponderosaand MPB-inested lodgepole pine

adjoin. This condition is occurring nearEstes Park, parts o Rocky MountainNational Park in Larimer County, near

Eldora in Boulder County, and nearEmpire, Georgetown and Idaho Springs.

In addition, CSFS oresters discoveredan MPB outbreak in ponderosa pine

orests near Virginia Dale in northernLarimer County in early 2009. This

outbreak is believed to have originatedrom inestations in lodgepole pine

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orests immediately west o this areaand now extends into Wyoming.Currently, the size o the averageinestation in this area is about 50 trees.

In recent years, the demand andavailability o markets or orest products

has declined. However, continuing eortsare being made to harvest trees killed

by MPB to reduce uels, remove hazardtrees and improve aesthetics. Mucho this work is occurring near homes,

road and power line rights-o-way, and

developed recreation sites. Salvaged treesare used or a variety o wood products,including lumber, house logs, urniture,wood pellets or uel, and bark chips

and mulch or landscaping. Blue-stain, adiscoloration o wood caused by a ungus

associated with bark beetles, producesattractive wood that has become popular

or urniture and paneling in homes andoces. Blue-stain pine also is popularor production o wooden bowls,

candlesticks and other novelty items.

Let: Lodgepole pines killed by mountain pine

beetle. Below: The pine engraver beetle, Ips

pini, is requently associated with mountain pine

beetle in lodgepole pine and can be ound killing

young trees.

The CSFS manages state orest trustlands, including the Colorado State

Forest, where a major MPB outbreakis underway. The CSFS has increased

management activities on the state orestover the last several years to address this

epidemic. The CSFS also is involved inlocal initiatives with organizations suchas the Colorado Bark Beetle Cooperative

and the Northern Front Range MPB

Working Group to identiy high-riskareas and implement treatments toreduce the threat o wildre. CSFS

district personnel have advised orestlandowners aected by the outbreakabout various orest management

options available to reduce losses. Theyalso have provided inormation on

available markets or bark beetle-killedtrees. In addition, the CSFS is working

closely with Colorado State Parks toimprove the health o orest land underits jurisdiction through long-term orest

management. This cooperative workdemonstrates that orest management is

compatible with extensive recreation use.

Spruce Beetle(Dendroctonus rupennis)

Spruce beetle aecting high-elevationEngelmann spruce orests has increasedthroughout the state. A total o 114,000acres o active spruce beetle inestationswere mapped in 2009, compared to

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64,000 acres in 2008. Most maturespruce orests on the crest o the RawahRange in northern Colorado and in theSan Juan Mountains near the headwaterso the Rio Grande River have beenseverely impacted by the outbreak;nearly 100-percent mortality o large-diameter trees has occurred in theseareas. In addition, spruce beetle activitywas detected in the high mountains

south o Wol Creek Pass, in the vicinityo Crown Point in the Never SummerRange and on the Grand Mesa.

Pure or nearly pure Engelmann

spruce orests occur at high elevations.Most o these orests are inaccessible byroad and/or are classied as wilderness

areas. These actors limit options orpest management or salvage o dead

trees. However, in some portions othe northern San Juan Range where

mature spruce was harvested about 40years ago, vigorous young stands o

spruce have re-established themselves.In June 2007, a high-wind event in

the Wet Mountains caused patches o

blowdown in Engelmann spruce orests.Spruce beetles readily invade wind-

thrown trees where they reach outbreaklevels and can attack standing trees. The

potential or a spruce beetle outbreakin this area is high. On Sept. 12, 2009,another blowdown occurred in orests

dominated by Engelmann spruce on theslopes o Del Norte Peak in Rio Grande

Top: This area o spruce blowdown occurred on the slopes o Del Norte Peak in Rio Grande County in

September 2009. Photo: Courtesy o the Rio Grande National Forest.Above: Spruce beetle outbreaks in

portions o the San Juan Range have killed most o the mature Engelmann spruce.

County. This blowdown also could causespruce beetle populations to spike.

Western Balsam Bark Beetle/Root Disease Complex

Subalpine r continued to die inhigh-elevation orests throughoutthe state. ree death is caused bywestern balsam bark beetle (Dryocoetesconusus) inestations, in combinationwith two ungi that cause root disease

(Armellaria spp. and Heterobasidiumannosum). Tis condition oen isreerred to as subalpine r decline.In 2009, subalpine r decline wasdetected on 184,000 acres o high-elevation orests, a substantial decreaserom the 346,000 acres detected in2008. Te decrease may be the resulto two seasons o heavy snowpack andnormal or above normal precipitation.

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2005

2006

2008

2009


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Other Bark Beetles

Other important bark beetles includeDouglas-r beetle (Dendroctonus

pseudtsugae), r engraver beetle

(Scolytus ventralis) and several specieso ips engraver beetles (Ips spp.).In 2009, an overall reduction

occurred in the area aected by

Douglas-r beetle. However, treemortality increased in portions o theRampart Range between Denver and

Colorado Springs. Several drainagescontained stands o 100 or more trees

with the red oliage characteristic otrees dying rom bark beetle attack.

(Local residents were concernedthat the MPB had reached epidemic

proportions in their area.) Douglas-rbeetle activity also was observed southo Paonia. Statewide, tree mortality

caused by the Douglas-r beetle wasdetected on 23,000 acres in 2009.

A localized outbreak o a twigbeetle, identied as Pityophthorusboycei, was detected in a bristlecone

pine (Pinus aristata) orest nearthe summit o Thirty-Nine Mile

Mountain in southeastern ParkCounty. Approximately 75 percent

o the new tree shoots were killed in

the most heavily inested areas.

Above: Douglas-r beetle galleries. Let: Twig

beetle adults, Pityophthorus boycei, in twigs o

bristlecone pine.

Deoliators

Western Spruce Budworm(Choristoneura occidentalis)

Western spruce budworm (WSBW) is

a major pest o Douglas-r, white r,Engelmann spruce and other coniersthroughout western North America.Larvae rst bore into the buds o theseconiers and later eed on the oliage onew shoots. During outbreaks, WSBWdeoliate millions o acres o trees. Forover a decade, WSBW has caused treedeoliation in southern Colorado andadjoining areas o New Mexico. In2009, WSBW deoliation in Coloradomore than doubled. Approximately

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382,000 acres o deoliation visiblerom the air were mapped, comparedto 155,000 acres in 2008. In 2009,deoliation occurred in portions o theCulebra, Flat op, Sangre de Cristo, SanJuan and Rampart ranges. Damagedorests have an overall brown cast, andyears o successive deoliation causesgrowth loss, top kill and tree death.

Pine Sawfy(Neodiprion autumnalis)

An outbreak o pine sawfy has beenunderway in the eastern-most ringeso ponderosa pine orests in ElbertCounty. Tis sawfy, identied asNeodiprion autumnalis, eeds incolonies on the needles o ponderosapine and has been active in this area orapproximately 8 years. Te adult wasplays eggs inside pine needles duringthe all. Winter is spent in the egg stage

the eastern United States during the late1800s. Every year, gypsy moth deoliatelarge areas o oaks and other broadleatrees in portions o the northeasternand north central United States, andsouth into the Appalachian Mountains.Gypsy moth moves easily rom placeto place because the larvae wi ll pupatealmost anywhere including thehubcaps o cars and emale mothscan lay eggs on almost any surace. Spotinestations have appeared in a numbero locations in the western United States,including Colorado. I gypsy mothwere to become established in the state,many species o broadlea trees in urbanareas would be threatened. In addition,native orests composed o Gambeloak, aspen and other broadlea treescould experience extensive deoliation.

Let: Aerial view o the deoliation o Douglas-r

and white r caused by western spruce budworm

in the Culebra Range. Below Let: Mature

western spruce budworm larva. Center: Pine

sawfy larva eeding on needles o ponderosa

pine in Elbert County. Bottom: Gypsy moth

detection trap. Photo: Ingrid Aguayo.

and the larvae hatch the ollowingspring. Numerous landowners in thearea have sprayed their pines withinsecticides to reduce deoliation.

Ponderosa PineNeedle Miner(Coleotechnites ponderosae)

For the second year, yellow discolorationo ponderosa pine needles causedby ponderosa pine needle minerwas detected in several areas along

the eastern edge o ponderosa pineorests. Te larvae o this insecteed inside pine needles and causethem to turn yellow and die.

The CSFS, in partnershipwith the USDA Animal Plant HealthInspection Service (APHIS) and USFS,uses a network o traps baited with an

attractant chemical known as Disparlurethat attracts male gypsy moths.

Entomologists use traps to determinei and where gypsy moth exist. In 2009,

two male gypsy moths were trappedin Adams County and one in PuebloCounty. More intensive trapping will

occur in these areas in 2010, and will

Exotic Pests

Gypsy Moth(Lymantria dispar)

Tis signicant deoliator o broadleatrees and orests was introduced into

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MarketingBeetle-Killed TreesDevelopment o viable markets or woodproducts rom trees ki lled by bark beet les

is an important aspect o managingthese orest insects. oday, more than90 percent o all wood used in Coloradois imported, either rom other states,Canada or Mexico. Tereore, manyopportunities exist to promote Coloradowood products and several initiativesare underway. For example, the CSFSColorado Wood Utilization and MarketingProgram (CoWood) acil itates retention,expansion and recruitment o orest andwood products businesses. CoWoodresponsibilities include research, technical and business assistance, andeducation and outreach. (http://css.colostate.edu/cowood/index.html). ColoradoForest Products (http://css.colostate.edu/cowood/cp.html) is a consumerawareness/product branding program unded by the CSFS or marketing woodproducts rom orest restoration and uels reduction eorts in Colorado orests.Te Colorado Forest Products logo can be used by businesses that obtain at least50 percent o the wood or their products rom Colorado orests. Te Peak toPeak Wood Program (http://www.peaktopeakwood.org) was created to movewood generated rom orest management projects on public and private landin Boulder, Clear Creek, Gilpin, Jeerson and Larimer counties into privatemarkets. Te program recently was expanded to help salvage MPB-killed timber.Peak to Peak operates several public wood collection and sort yards whereinested logs can be delivered. Revenues obtained rom sale o bark beetle killed

trees currently are tax exempt.

Above:Emerald ash borer. Photo: David Cappaert.

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Protecting Colorados WatershedsWater is a critical resource or drinking,irrigation, industry and recreation.

In Colorado, where the average yearlyprecipitation is about 17 inches, water isscarce and perhaps is our most criticalresource. wo successive years o above-average snowpack, combined with a wetspring and early summer in 2009, turnedour hills emerald green and helped llthe states reservoirs. Early in 2009,reservoir storage volumes were at 116percent o capacity the highest storage

volume since 1999. However, just a ewyears ago, our reservoirs were ar belowcapacity, resulting in restricted water use

or many Colorado communities. Wateris a resource that must be careullymanaged to meet the needs o Coloradosresidents, as well as those who live inneighboring states.

High-elevation orested watershedsare the source o most o Coloradoswater. They orm the headwaters o

our o Americas major rivers theArkansas, Colorado, Platte and Rio

Grande. These rivers provide water to 18states, in addition to Colorado. Most o

our precipitation arrives during winter as

snow and is stored on mountain slopesas snowpack. With the arrival o warm

weather in spring, the snow melts andfows downstream into a network o

reservoirs that store water or domestic,agricultural and industrial uses. I warm

temperatures arrive too quickly, thesnowpack melts too ast. As a result,

streams become swollen and may foodtheir banks with resultant damage toproperty and inrastructure. Forest cover

is critical or protection o water qualityand quantity. Forests provide shade that

slows the rate o spring snow melt, andthe roots o trees, shrubs and grasses bind

the soil to help prevent erosion, whichcan signicantly reduce water quality.

Protecting orests rom damaging

agents such as re, and insect anddisease outbreaks will help maintain

and enhance water quality and yield.

The 2002 Hayman Fire burned morethan 138,000 acres in the South PlatteRiver Basin. Burned surace vegetationand the ormation o hydrophobic soils

caused increased surace runo, whichtransported sediment during heavy rains

causing severe soil erosion. This, in turn,caused siltation and reduced the drinking

water quality o Cheesman and StrontiaSprings reservoirs, important sources odomestic water or the greater Denver

area. Heavy soil erosion and mudslidesin the Hayman burn area have aected

the dynamics o the landscape. In July2009, or example, heavy rains over

sections o the burned area caused severemudslides in the vicinity o Deckersand temporarily blocked State Highway

67. This ollowed fooding in previous

years that caused severe damage to thehighway, kept it closed or months and

cost $11,000,000 to repair.The massive MPB outbreak currentlyunderway in lodgepole pine orests o

northern Colorado also could aectwater quantity and quality. As trees die

and all, orest cover becomes less dense,allowing greater exposure o snowpack

to solar radiation, causing aster runoand increased soil erosion. Grand Lake,west o Rocky Mountain National Park,

is at the epicenter o the current MPBoutbreak. It also is the source o water

or heavily populated areas on thenorthern Front Range. Water rom Grand

Lake is carried eastward via a networko tunnels under Rocky MountainNational Park and national orest lands,

and eventually reaches HorsetoothReservoir west o Fort Collins. The

long-term eect o the MPB outbreakon the quality and quantity o domestic

water is not yet ully understood.Eective management and protection

o Colorados orests, based on soundscience, is integral to the protectiono the states watersheds and water

supplies. These practices will help ensurea sustainable supply o water to meet

present and uture needs.

Above: In addition to providing water, reservoirs

provide opportunities or recreation including boating

and water skiing. Let:Areas burned by the 2002

Hayman Fire are still subject to soil erosion, as this

photo indicates. Photo: Meg Halord.

Special Issue

Watersheds


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Pion-Juniper Woodlands:A Unique EcosystemCovering a total land area o more than48 million acres, the pionjuniper(PJ) woodland o the Southwest is themost extensive orest cover type in thewestern United States. Colorado hasapproximately 5.3 million acres o PJwoodlands, which comprise roughly 28percent o the states total orest area.PJ woodlands consist o short, scrubby,oen multi-stemmed trees that mayappear inhospitable this is ar romaccurate. Tese woodlands provide

essential habitat or mule deer, a varietyo smaller mammals and many specieso birds, reptiles and insects. Tey alsoare home to many fowering plantssuch as the prickly pear cactus with itsbrilliant red, pink and yellow spring andearly summer blossoms. In addition,pion pine nuts once were a staple oodo indigenous tribes that lived in theSouthwest. oday, they are considered adelicacy and are an ingredient in manypopular regional dishes.

In Colorado, PJ woodlands are

ound rom just south o Colorado

Springs, south and west to the Four

Corners region. PJ woodland also is amajor orest type in the lower elevations

o the Western Slope. They occupylow-elevation sites that are too dry orlarger trees such as ponderosa pine

and Douglas-r. One species o pion,the New Mexico pion (Pinus edulis),

and three species o junipers constituteColorados PJ woodlands. In the eastern-

most areas, Rocky Mountain juniper(Juniperus scopulorum) and one-seed

juniper (Juniperus monosperma) are

the dominant junipers. Utah juniper

(Juniperus osteosperma) with itscharacteristic dark green oliage is thedominant juniper o PJ woodlands on

the Western Slope. In addition, Gambeloak (Quercus gambelii) oten is ound in

these woodlands.Pion-juniper woodlands are a major

component o several o the states crownjewels, including the Colorado National

Above: Pion-juniper woodlands are the dominant

vegetation in the Colorado National Monument.

Let: The collard lizard, Crotophytus collaris, is one

o the many residents o Colorados pion-juniper

woodlands. Above Let: Prickly pear cactus, with

its bright blossoms and many colors, is a common

plant in pion-juniper woodlands.

18


Pion-Juniper Woodlands


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Monument, Mesa Verde National Park,

and the Great Sand Dunes National Parkand Preserve. These woodlands also have

become popular homesites or peoplewho wish to live in a rural setting.

Like all o Colorados orests, PJwoodlands are dynamic and subjectto disturbances caused by re, insects

and disease. Wildre is integral to thedynamics o these woodlands. For

example, since Mesa Verde National Parkwas established in 1906, 80 percent o

the parks orests have burned. In 2000,wildres burned more than 20,000acres o the parks PJ and Gambel oak

woodlands. An outbreak o the pionips (Ips confusus) bark beetle killed large

numbers o pions between 2002 and

2003. The ollowing sections highlightsome o the key pests o PJ woodlands.

Pests o Pion-JuniperWoodlands

Pion Ips(Ips conusus)

Tis bark beetle, a relative o the MPB,breeds under pion bark and kills thetree. Attacks occur in weakened treesand outbreaks usually ollow periods obelow-normal rainall. During the dryyears o 2001-2003, this insect killedmillions o pion in southwestern

Colorado and adjoining states. At thepeak o the outbreak in 2003, aerialsurveys indicated that 4.2 million pionwere kil led on approximately 937,000acres. In southwestern Colorado,

many woodlands lost 90 percent o themature pion. Te heaviest inestationsoccurred near Durango, Cortez andDolores. Further north, inestationswere more scattered with some areas olocalized tree mortality. Te outbreakhas subsided in recent years as higherlevels o precipitation have occurred.



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Twig Beetles(Pityopthorus spp.)

wig beetles are bark beetles that breedin and eed on the stems and twigs otrees. Several species o twig beetlesattack pion pine and damage oen isseen in areas where pion ips beetle isactive. wig beetles usually do not killentire trees, but the crown may sustainsignicant damage during periods oheavy inestation.

Pion Needle Scale(Matsucoccus acalyptus)

Nymphs and adults o pion needlescale eed on the tender shoots andone-year old needles o pions. Tedamage causes loss o older oliage,weakens trees and makes themsusceptible to attack by pion ips.During 2009, pion scale inestationswere reported in Huerano County.

Right: A lone juniper clings to a rock ace at the

Colorado National Monument. Below:A pion

shoot killed by a twig beetle. Bottom Let: The

sawfy,Zadiprion rowheri, is one o two sawfies

known to deoliate pion pine. Bottom Right:

Galleries o a juniper bark beetle, Phloeosinus sp.

Sawfies(Neodiprion edulicolis and

Zapdiprion rowheri)

Te larval stage o a sawfy is similarto a caterpillar, but the adult is a smallwasp. wo o these species eed on theneedles o pion pine and occasionallyreach epidemic levels. Large numberso larvae strip the trees o theiroliage. In 2007, one o these sawfies,

Zadiprion rohweri, deoliated pion inMesa Verde National Park and otherareas o southwestern Colorado.

Juniper Bark Beetles(Phloeosinus spp.)

Several bark beetles attack junipers,breed under the bark and kill the trees.Tey usually conne their attacks torecently cut or weakened juniper andmay kill healthy trees during extendeddry periods.

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Colorados Urban Forestsrees are essential to our quality olie. Tey add beauty and harmony towhat otherwise would be a harsh, coldlandscape. rees planted along streets,

parks and greenbelts provide welcomeshade rom the summer sun andpeaceul places to walk or simply relax.Tey lter the noise o heavy trac andragment heat islands created whenthe suns radiation is absorbed by tallbuildings. rees help reduce levels ocarbon dioxide and other greenhousegases in the earths atmosphere that cancontribute to global climate change.

In Colorado, urban orest ecosystemsare composed almost entirely o exotictrees. Many o our most popular shade

and ornamental trees such as linden,white and green ash, honey locust, and

Norway and silver maples are nativeto the eastern United States or Europe.

Even our own quaking aspen, a Coloradonative, occurs naturally at elevationsthat are higher than most o our urban

orest communities. Many o Coloradosurban orests occupy what once was the

short grass prairie, an ecosystem totallydevoid o trees except or the occasional

cottonwood along stream bottoms.

The health and vitality o urban

orests requires vigilance, care andregular maintenance. Colorados

semi-arid climate requires that

urban trees be watered regularly,including during winter months when

prolonged dry periods may occur. Avariety o biotic and abiotic agents

can damage our urban orests.Because many trees planted in

Colorados urban orests are exotic, mosto the pests that damage these trees alsoare exotic. These trees and pests typically

come rom the eastern United States andCanada, Europe or Asia. Fortunately,

much o the damage these agents cause,such as lea deormities and galls by

insects and mites, is cosmetic; however,signicant exceptions do exist. (One suchexception is Dutch elm disease. Caused

by the ungus Ophiostoma ulmi, whichwas introduced into the eastern United

States during the 1930s, Dutch elmdisease since has killed thousands o elm

trees.) Several recent pest introductions,including the Asian longhorn beetle(Anoplophora glabripennis) and the

emerald ash borer (Agrilus planipennis)have caused signicant damage in

parts o the eastern United Statesand Canada, and pose a signicant

threat to Colorados urban orests.An eective long-term strategy to

minimize the impacts o damagingurban tree and shrub pests is to plantas great a variety o species as local

conditions will allow. Because bioticpests (insects, mites, ungi, etc.) are

relatively host specic, only a portiono the trees would be susceptible should

a new pest appear. Many communitieslearned this lesson rsthand when Dutch

elm disease established itsel in NorthAmerica. Prior to the introduction othis devastating disease and its principal

insect vector, the smaller European elmbark beetle (Scolytus multistriatus),

many communities in the central UnitedStates relied heavily on the stately

American elm (Ulmus americana) as ashade tree. Once the disease began tospread, these communities lost all o

their shade trees within just a ew years.Damaging or not, urban tree pests

are o concern to many homeowners.

The CSFS, in partnership with ColoradoState University Extension and cityoresters, provides technical assistanceto communities to identiy and manage

tree pests. The ollowing section providesbrie descriptions o some o Colorados

more common urban tree pests.

Thousand CankersDisease o Black Walnut

Tousand cankers disease was recentlydiscovered in Colorado. Tis potentially

signicant disease o black walnuthas been kil ling trees in Coloradoand other parts o the western UnitedStates. Te disease is likely causedby multiple ungi (Geosmithia spp.)and is spread by a walnut twig beetle(Pityophthorus juglandis). Te beetleis native to Mexico, Arizona, a smallarea in southern Caliornia and NewMexico where it causes minor damage toArizona walnut. Te range o the diseasecurrently is expanding in Caliornia,

Let: Ammons Hall in the summer on the Colorado

State University campus oval. Many trees on campus

are now over 100 years old. Photo: Bill Cotton.

Special Issue

Urban Forests


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and now has reached Colorado, Idaho,Oregon, Utah and Washington whereit is attacking the ornamental blackwalnut tree (Juglans nigra), a new host.Te beetle is more aggressive on black

walnut, has developed an associationwith the Geosmithia ungus and carriesthe ungus rom tree to tree. Te unguscauses cankers, which restrict the fowo nutrients and can kill t rees withina year. Tis insect/ungus associationhas killed many black walnut trees inBoulder and Colorado Springs. I thisinsect spreads east into the natural rangeo black walnut, where lumber producedrom this tree is widely used orurniture, gunstocks and other specialtyproducts, losses could be devastating.

In 2009, new inestations were

detected in the Denver Metro areaincluding Arvada, Aurora, Brighton,

Denver proper, Golden, Westminsterand Wheat Ridge. The disease alsohas been conrmed in Berthoud, Erie

and Longmont. It has been presentin Grand Junction or several years

and was recently detected in Delta onthe Western Slope and in Rocky Ford

and Olney Springs east o Pueblo.

Other Pests o Urban TreesOystershell Scale(Lepidosaphes ulmi)

Tis insect is one o the most commonurban tree pests and can inest anumber o species including aspen,ash, cotoneaster and lilac. Largecolonies eed on the smooth bark otrunks and branches. Aer severalyears o eeding, the inested barkdries and cracks. Te scales arearmored and when examined under

magnication resemble a tiny oyster.

Lilac-ash Borer(Podesia syringae)

Te larvae o lilac-ash borer tunnel inlarger branches and trunks o ash, lilac

and privet, and heavy inestations cankill branches. Te adults are moths withtransparent wings and resemble wasps.

present nearly every year. Duringheavy inestations, the entire leamay be covered with galls. Tey arenot damaging, but the curled leavescovered with gal ls are unattractive.

Banded Elm Bark Beetle(Scolytus schevyrewi)

Native to China, Mongolia, Russiaand portions o central Asia, this barkbeetle was rst detected in Colorado

and Utah in 2003. It attacks elms andother broadlea trees and is closelyrelated to the smaller European elmbark beetle (Scolytus multistriatus),which spreads Dutch elm disease. Tebeetle now is known to occur overmuch o the central and western UnitedStates and has attacked and killed elmsin Fort Collins and other Coloradocommunities during dr y summers.Its role as an agent that spreadsDutch elm disease still is unclear.

Iron Chlorosis

Tis problem is common in manyurban trees. Iron is an essentialelement or plant growth and inColorados alkaline soils it is not alwaysavailable to the plant. Symptoms oiron deciency include yellow leaveswith green veins, subsequent dead

patches on leaves and eventual branchdie-back. Silver maple and quakingaspen are especially susceptible to ironchlorosis, but the condition can occuron many other trees and shrubs.

Hackberry Nipple Gall(Pachypsylla celtismamma)

Hackberry nipple gall producesprominent wart-like galls on theleaves o hackberry trees, and nymphsdevelop inside the galls, which are

Let: Damage caused by lilac ash borer to an

ash tree; note pupal cases protruding rom bark.

Center:Yellow oliage and green veins on silver

maple are typical symptoms o iron chlorosis.

Below: Galls on hackberry caused by hackberry

nipple gall. Below Let: Inestation o oystershell

scale on a young aspen.

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Urban Forests


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How did the beetles arrive? Tey likelywere transported on winds during thebeetles summer fight.

The invading beetles have a denitepreerence or Scotch pine (Pinussylvestris), a tree native to Europe and a

popular ornamental tree in many Front

Range communities. Other aectedpines included Austrian, eastern white,ponderosa and even mugo pine.

Fortunately, only a small number obeetle-inested trees were discovered inFort Collins. City oresters inventoried

many pine trees and identied morethan 300 trees that were attacked by

beetle, but only about 20 pines actuallywere inested. The remaining pines were

vigorous enough to repel the invadingbeetles with resin. (The ability o a tree toevict invading beetles with resin is known

as a pitchout.) By mid-winter, successulattacks could be readily identied

by missing pieces o bark caused bywoodpeckers that eed on the larvae and

pupae. Needles o successully attackedpines began to ade by mid-March;

these trees were removed and chipped toensure that the next generation o beetleswas killed beore they could emerge, fy

and attack additional trees.MPB continued to invade urban

orests in 2009; by August, additional

MPB attacks were reported in Brighton,

northeast Denver, Fort Collins andGreeley. Attacks also were ound in pine

planted in communities as ar east asSterling. Again, many o the beetles were

pitched out beore they killed the trees.


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Quaking aspen, Populus tremuloides,is one o Colorados most popular

trees. Aspen orests occupy about 2.2million acres o our state. A Coloradocommunity, myriad streets, children,pets, even a beer, have been named aerthis legendary tree. Aspen diversiesour orests, otherwise dominated bydark pine, spruce and r. Aspen orestsare open, allowing sunlight to reachthe orest foor. In turn, the sunlightencourages many wildfower speciesincluding columbine, Coloradosstate fower, to thrive. Tey also are

An Update on the Health ofColorados Aspen Forests

a preerred habitat or elk and otherwildlie. Mature aspen stands oer

abundant orage or elk while youngerstands oer cover or hiding rompredators. In autumn, aspen-coveredhills are ablaze with brilliant hues oyellow, gold and orange. Tis spectaculardisplay o all color attracts thousandso visitors and is one o the key reasonstourists travel to Colorado in autumn.

Sudden Aspen Decline

During the past decade, many oColorados aspen orests have been

dying. Tis has caused concernamong orest health and resource

management proessionals, as wellas the general public. Over thepast three years, the location andintensity o areas o dead and dyingaspens has been mapped during theannual orest health aerial survey.

The recent episode o aspen mortalityhas been reerred to as sudden aspen

decline or SAD. Decline or diebackis a complex condition that usually iscaused by several interacting biotic and

abiotic actors, and may contribute to


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the dynamics o some orests. Prolongeddrought, outbreaks o deoliating insects

or ungi that cause root disease areamong the actors that can be involvedin orest decline. Decline and dieback

o orests are a worldwide phenomena,and occurrences have been reported in

North America, Arica, Asia, Europe andSouth America. Symptoms o decline

are progressive and may include reducedgrowth, smaller than normal oliage, thincrowns, branch dieback and tree death.

Three classes o actors typically areinvolved in decline:predisposing, incitingand contributing. Predisposingactorsare long-term conditions such as stand

age or occurrence o root-inestingungi, which stress trees and orestsover many years. Incitingactors are

short-term conditions such as drought,excess rainall, late spring rost or

outbreaks o deoliating insects. These

conditions place additional stress onalready weakened trees and can causecrown thinning or dieback. Contributingactors consist o attacks by insects, such

as secondary bark beetles or wood-borers, or ungi, which are unable to

attack and kill healthy, vigorous trees.In the American Southwest, quaking

aspen colonizes large areas as pure,even-age stands, usually ollowing adisturbance such as re. Because o

Colorados semi-arid climate, aspen

seeds have a low germination rate.Thereore, aspen orests occur as the

result o a ew trees that originate romseed and produce runners and sprouts.Aspen orests mature at about age 60,

but many aspen orests in the Southwestare over 100 years old. At low elevations,

where growing conditions are too dryor coniers, aspen stands are the climax

orests. The understory usually consistso a dense cover o aspen seedlings thatare ready to replace the older trees as

they die. At higher elevations, aspen isa pioneer species and eventually gives

way to spruce, r and other coniers.As aspen stands mature, their growth

rates decline and they are subject toungal inections. Recent episodes obelow-normal moisture, late spring rost

and outbreaks o deoliating insects such

as western tent caterpillar and large aspentortrix have placed additional stresson aspen orests, thus causing decline.

Several ungi and insects such as thebronze poplar borer (Agrilus liragus) and

at least two species o bark beetles haveattacked and killed weakened aspens.

Most aspen orests aected by recentdecline occur at the lower elevationallimits o tree growth where aspen is a

climax species. Dead trees oten occurin bands or waves, appearing rst at

the orest edge and then progressinginward. In other orests, dead and

declining trees are scattered throughoutthe stand. Many aected stands exhibitdense aspen regeneration in the

understory. Once exposed to sunlightand space, aspen seedlings grow aster

and eventually replace dead and dyingtrees in the overstory. However, many

climax aspen orests lack naturalunderstory regeneration, oten becausethey have been subject to overgrazing

by elk, deer or domestic livestock. These

stands likely will revert to grasslandvegetation when the mature aspens die.Managing and protecting young

seedlings that grow in the understoryo aspen climax orests is essential tothe uture o Colorados aspen. This

includes timely harvesting o matureaspen stands to release the seedlings

beore stands become too stressed toproduce vigorous natural regeneration.

In addition, aspen regeneration shouldbe protected rom overgrazing by

domestic animals, deer and elk.

In 2009, approximately 342,000acres o aspen overstory mortality were

mapped during the orest health aerialsurvey, compared with 542,000 acres

in 2008. In many areas, patches o deadaspen appeared less distinct in 2009 and

some aspen orests with previously thincrowns during the past ew years appearto have recovered. Additionally, where the

aspen overstory had died, the understoryregeneration is growing rapidly in many

stands. These observations, in addition to

Opposite: Aspen oliage at the peak o all

color. Let:A mountain cabin sits among

aspens at the peak o all color near

Pingree Park. Below:Aspen in the all.

Special Issue

Aspen Update


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two winters o above average snowpackand an unusually wet summer in 2009,

suggest that the current episode o aspendecline may be slowing. (See map page

10 for areas affected by aspen decline.)

Other Factors That AectAspen Forest Health

Western Tent Caterpillar(Malacosoma caliornicum)

Western tent caterpillar is the mostcommon insect deoliator o aspenorests in Colorado. Te larvae emergerom eggs in spring, just as the budsburst, and build silken tents in thecrowns o inested trees to protect them

against natural enemies and weather.Larvae eed rst in colonies and later asindividuals. Outbreaks can strip treeso their oliage within just a ew weeks.Te larvae then migrate to other sitesto continue eeding. During the 1970s,migrating western tent caterpillars madethe Cumbres and oltec Railroad tracksso slick that the engine was unableto gain traction and climb the steep

mountain grades. Successive years odeoliation by western tent caterpillarcan cause branch dieback and tree death.

Over the past 5 years, western

tent caterpillar outbreaks have

deoliated aspen orests on thousandso acres in southern Colorado.In 2009, deoliation caused bywestern tent caterpillar occurred in

portions o the Culebra, Sangre deCristo and San Juan mountains.

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In northern Colorado, western tentcaterpillar is a common deoliating

insect o several woody plants, includingbitterbrush, choke cherry, wild currant

and mountain mahogany. It is oundonly occasionally on quaking aspen.

its own. In 2009, an outbreak olarge aspen tortrix was detected onRed Mountain Pass near Ouray.

Late Spring Frost

Frosts that occur at the time o budburst or early lea development cankill buds, damage oliage and destroyfowers o trees and other woody plants.In Colorado, aspen orests, especiallythose growing at high elevations,

oen are subject to late spring roststhat essentially have the same eecton trees as deoliating insects. In2007, a widespread late spring rostaected many aspen orests, especiallyon Colorados Western Slope.

Marssonina Lea Blight(Marssonina populi)

Marssonina lea blight is a diseasecaused by a ungus that inects theleaves o aspen and other cottonwoods.

Symptoms include dark brown fecksand yellow margins on the leaves. Teinected areas oen merge to ormblotches o discoloration. Inectedaspen stands may have an orange castduring the middle o the growingseason when the oliage should be green.

Large Aspen Tortrix(Choristoneura confictana)

Large aspen tortrix is related to theWSBW. Te larvae roll aspen leaveson which they eed and tie them withsilken webs to provide protection romnatural enemies. Tis insect oen isassociated with western tent caterpillar,but can develop into outbreaks on

Aspen clones show varying levels osusceptibility to this disease. By theend o the growing season, some clonesexhibited near-complete deoliation.In 2009, occurrence o this diseasewas reported in several areas o thestate and was particularly prevalentin the Red able Mountain and

Grand Mesa areas. Te developmento this ungus undoubtedly wasencouraged by the wet weather thatcharacterized the 2009 growing season.Aspen stands aected by this diseaselikely will recover unless repeateddeoliation occurs or several years.

Special Issue

Aspen Update


30/40

Climate, Forests, Fire,Humans and Insects:

A Complex InteractionColorados orests are dynamic; theircharacter is shaped by disturbancescaused by climatic events such asdrought or severe storms, wildre,humans and insects. Our orests growin a semi-arid climate where averageannual precipitation is between 11and 17 inches at the low elevations toabout 45 inches near the upper limitso tree growth. As a result, these orests

contain relatively ew tree species. Temost commonly occurring trees are a llmembers o the pine amily (Pinaceae):ponderosa, lodgepole, limber, bristlecone

and pion pines in addition to coniers,such as Douglas-r, blue and Engelmannspruce, and white and subalpine r.Quaking aspen and Gambel oak areamong the ew broadlea species oundin Colorados orests. Many o Coloradosorests are composed o stands with onlyone or two species.

Climate, especially moisture,

determines which tree species will grow

at a given location. Generally speaking,as elevation increases, so does availablemoisture. Thereore, trees are conned

to specic elevation or moisture zones.

Pion pine and juniper woodlands

dominate the lowest elevations and beginat approximately 4,100 eet. As elevationincreases, these woodlands transition

into pure orests o ponderosa pine. As

elevation and available moisture increase,mixed conier orests with Douglas-r,and in southern Colorado, white r, will

occur in combination with ponderosapine. On north acing slopes, whichreceive less direct sunlight and have

a cooler, moister climate, Douglas-rappears at lower elevations more so

than on south acing slopes, which arewarmer and drier. In northern Colorado,

ponderosa pine/Douglas-r orestsusually are replaced by pure, even-agedorests o lodgepole pine at around 8,000

eet. At elevations o around 9,500 eet,subalpine r and Engelmann spruce

are the dominant trees. As elevationcontinues to increase, the proportion


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o Engelmann spruce also increases; atapproximately 11,500 eet (the upperlimit o tree growth), nearly pure stands

o this species exist.Fire is an integral dynamic o

Colorados orests. Size, requencyand intensity o res are actors

that determine the character oour orest landscapes. Colorados

orests are subject to prolongeddrought, oten accompanied bydry lightning, which may trigger

wildres that can burn either smallpatches or thousands o acres. Human

activities such as leaving campresunattended or carelessly discarding

cigarette butts also cause wildres.

Our native trees have developedadaptations that allow them to coexist

with wildre. Ponderosa pine, orexample, has a relatively long lie span,

oten reaching 300-600 years o age.Large, old ponderosa pines have a thick

bark that insulates them rom high

temperatures and allows them to survivelow-intensity surace res. Prior tohuman settlement, natural re intervalso between 1 and 50 years occurred in

many ponderosa pine orests. Theseres typically were low-intensity surace

res that consumed branches, allentrees, understory vegetation and small

living trees. They produced a landscapeo open, park-like orests, composed olarge pine trees with a grass understory.

Along the Front Range, ponderosa pineorests tended to be a mosaic o orests

and meadows. A combination o low-intensity surace res and hotter stand-

replacing res that killed most or all othe trees may have created these mosaics.

Lodgepole pine, on the other hand,

has developed a dierent adaptation tore. This tree has a relatively short lie

span, and most stands are consideredmature at about age 60 to 100 years.

Higher moisture levels and coolertemperatures mean the natural reinterval in lodgepole pine orests can vary

rom 60 to well over 100 years. Lodgepolepine bark is thin and, thereore, unable

to protect the trees rom re. Lodgepolepine produces both non-serotinous and

serotinous cones. Serotinous cones openonly when exposed to high temperatures.

When wildre occurs in a lodgepole pine

orest, most or all o the trees are killed.As re burns through the orest, high

temperatures cause serotinous cones toopen, releasing abundant seeds to start a

new orest. High-elevation subalpine rand Engelmann spruce orests also are

subject to large, high-intensity, stand-replacing res, but the average re-returninterval is much longer oten well over

200 years.Humans have had a proound impact

on natural re intervals in the orests othe western United States. Indigenous

tribes used re to drive game and clearland to grow ood. Many years later, inthe early 1900s, an aggressive wildre

suppression program began ollowinga series o disastrous wildres caused

by a combination o drought, humansettlement and dense re-growth ater

timber harvesting. As a result, naturalre was either excluded or the re returninterval changed signicantly, especially

in areas where res historically burnedevery 10-50 years. Consequently, uel

Let: A young lodgepole pine stand develops

in the atermath o a stand-replacing re in

Yellowstone National Park. Below: Serotinous

cones on lodgepole pine do not open until

exposed to high temperatures.

Distribution o Key Forest Vegetation Types by Elevation andSlope in Northern Colorado

Above treeline

Engelman spruce

Subalpine fr/Engelmann spruce

Lodgepole pine

Ponderosa pine/Douglas-fr

Douglas-fr

Ponderosa pine

Rocky Mountain juniper

Feet

Special Issue

Interaction


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levels, species composition and thenumber o trees per acre changed. In

ponderosa pine orests, their open,park-like character changed due to re

exclusion; these orests now containmany more trees per acre. In otherareas, ponderosa pine orests have been

replaced by Douglas-r and white r asre exclusion encouraged the growth o

less re-tolerant species.A recent analysis o the re history

and orest dynamics in areas aectedby the 2002 Hayman Fire, the largestwildre in Colorados recorded history,

illustrates the eect o re exclusion onwestern orest landscapes. The analysis

indicated that between 1300 and 1880,average interval between naturally

occurring res was about 50 years,although some res occurred almost

every year. The results illustrated amosaic o both stand-replacing res and

lower-intensity res in which the larger,older trees survived. No major res

occurred in the area between 1880 and2002; rom 1900 to 2002, a lack o re

activity resulted in a signicant change inspecies composition and an increase inorest density.

Increased re-return interval periodsnot only changed the composition

o these orests, they also changed

susceptibility to insect outbreaks.Ponderosa pine orests, which noware more densely stocked, are more

susceptible to MPB outbreaks. In areas

where ponderosa pine has given way toDouglas-r and white r, outbreaks odeoliating insects such as WSBW and

Douglas-r tussock moth have becomemore requent and widespread. Olderlodgepole pine orests with a high

proportion o trees greater than 6 inchesin diameter that have relatively thick

bark provide a wealth o excellent hostmaterial or MPB.

Climate, re exclusion and aginglodgepole pine orests have ostered a

perect storm resulting in the massiveMPB outbreak currently underway inColorado. Fire exclusion resulted in

the occurrence o extensive areas opine orests with such characteristics as

large-diameter trees and dense standsthat are susceptible to MPB. The drought

that began in the 1990s and severelyincreased in 2000 stressed the trees andmade them more susceptible to beetle

attack. In addition, prolonged coldwinter temperatures o 30 to 35 F or

less, which occurred regularly in high-

elevation lodgepole pine orests killingbeetles that overwintered under the bark,

Above: Fallen trees rom an old mountain pine beetle outbreak provide ground uels to support a stand-

replacing re in a lodgepole pine orest.

Above treeline

Engelman spruce

Subalpine fr/Engelmann spruce

Mixed conier

Ponderosa pine

Pion-juniper

Distribution o Key Forest Vegetation Types by Elevationand Slope in Southern Colorado

Feet

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have not occurred during the last decade.

Consequently, a higher proportion ooverwintering beetles are surviving.

Many people are concerned that the

current MPB outbreak will increase the

probability o a catastrophic wildre.Bark beetle epidemics leave thousands odead trees in their wake and change the

character o orest uels. Dead standinglodgepole pines with red needles andne dead branches can carry intensive

wildres. However, ater a ew years, theneedles and ne branches drop rom the

trees. During this period, res that dooccur are likely to be less severe. Over

time, many o the beetle-killed trees willall and new trees will grow, creating

conditions avorable or res capable oburning large areas. An accumulation

o downed trees makes re suppressionmore dicult and compromises thesaety o reghters and high-country

residents and visitors.The massive wildres in and around

Yellowstone Park in 1988 provide insightinto the interaction between MPB

outbreaks and wildre. Approximately 36percent o Yellowstones total orest area,dominated by lodgepole pine, burned

ater the driest period in the parksrecorded history. Prior to the 1988 res,

the park and surrounding areas enduredtwo MPB outbreaks one between 1972

and 1975 and another between 1980

and 1983. An analysis o the relationship

between the Yellowstone res and theearlier MPB outbreaks shows that areas

aected by the rst outbreak (13 to16 years prior) were approximately 11percent more likely to burn. However, no

correlation was made between the secondMBP outbreak (5 to 8 years prior) and

the probability o burning. Scientists whoconducted the study contend that one

o the reasons the older outbreak areaswere more likely to burn was that enough

time had passed to allow the understoryvegetation to grow, providing ladder uelsthat increased re risk and intensity. A

Above: Relatively requent low-intensity ground

res help create open, park-like stands o

ponderosa pine. Let: Small clearcuts in lodgepole

pine orests easily regenerate and create a mosaic

o stands composed o dierent age classes

including younger stands that are less susceptible

to mountain pine beetle attacks.

similar study in Utah suggests that withinapproximately 10-20 years ater a spruce

bark beetle outbreak, wildre risk was

lower in those orests that suered heavymortality (greater than 95 percent) thanin unaected orests. The potential or asevere re increases as dead trees all and

young trees become established in theatermath o the outbreak, thus providing

the ladder uels necessary to supportdevastating wildres.

While these studies suggest thatthe probability o a catastrophic re inareas aected by bark beetle outbreaks

may not be as high as expected in theshort term, the potential or wildre

occurrence, especially during periodso prolonged drought, remains a major

concern. Prompt detection and eectivemanagement o wildres is critical. Forestmanagement tools also are important

and may include prescribed re to reduceuels and stocking levels, and thinning

and timely harvesting o mature treesto support restoration. This is especially

true or those areas in which re-returnintervals have been altered due to activere suppression.

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2009 Forestry-RelatedLegislation in ColoradoColorado values healthy, resilient orestlandscapes, and the states legislatureis willing to invest unds in thestewardship o these resources. In 2009,the Colorado General Assembly passedseven bills addressing orest health,uels mitigation and public saety. Tislevel o legislative activity is evidence othe importance and value o Coloradosorests. Te legislation is aimed atcreating legislation to promote healthier,more diverse orests that are resilient

to insect and disease epidemics or thebenet o present and uture generations.

HB07-1130 CommunityBased Forest Restoration

In 2007, the Colorado General Assemblypassed HB 07-1130, the Community-Based Forest Restoration Program. Tis

legislation authorized up to $1 millionper year over 5 years to und a cost-share grant program or community-based orest restoration projects inColorado. Te projects are designedto protect critical water supplies andaddress related orest health issues.

The Colorado Department o NaturalResources (CDNR) appointed a Technical

Advisory Panel to review the proposalsand recommend project unding. The

panel included representatives rom

the CDNR, two ederal agencies (USFSand Bureau o Land Management), twoindependent scientists with expertisein orest ecosystem restoration,

and representatives o conservationorganizations, local communities

and commodity interests.Funds were provided to CDNR

and subsequently to the CSFS via an

Bill Number Bill Name Bill Summary

SB 001Community WildreProtection Plans

CSFS will establish guidelines and criteria or counties to consider in preparing

community wildre protection plans (CWPPs) to address wildres in re hazard

areas within the unincorporated portion o a county.

SB 013Civil Immunity to PersonsEngaged in EmergencyResponse Activities

Enacts the Marc Mullenix Volunteer Fireghter Protection Act, providing limited

civil immunity or re departments and other entities that donate surplus reghting

equipment or later use; volunteer reghters, their commanders, and the

organizations that employ them; and incident management teams, in connection

with res and other emergencies.

SB 020Responsibility or Respondingto Wild Land Fires

Creates a systematic, proactive approach to the management o wildland re

incidents in Colorado, regardless o cause, size, location, or complexity.

SB 021Incentives or VolunteerFireghters

Creates a und in the division o re saety to provide tuition vouchers to qualied

volunteer reghters who are enrolled in ull-time or part-time study and who agree

to serve as volunteer reghters or 4 years ater completing their education.

SB 105Removal o Statutory Limit on theamount that may be raised orthe purpose o ghting res

Removal o the statutory limit on the amount that can be raised in a year by a

special property tax levied by a board o County Commissioners or the purpose o

ghting specied types o res in a county.

HB 1162IntergovernmentalCooperation or the Purposeo Mitigating Wildres

On or beore a specied date, requires each local government that owns any

land area that is located either entirely or partially inside the territorial boundaries

o a county and that contains a specied percentage o orest land or land that

constitutes a wild land area to enter into an intergovernmental agreement with

the county or the purpose o mitigating orest land or wild land res aecting the

contiguous land areas o the local government and county.

HB 1199Colorado Healthy Forests andVibrant Communities Act o 2009

Increases eorts to address wildre risk, and provides resources to the Colorado

State Forest Service to augment its technical outreach capabilities and provide loans

and grants or market-based and orest treatment solutions to reduce wildre risk.

interagency agreement. Once the undingmechanism was in place, the CSFSissued a request or proposals in June

2007 and announced the grant awardeesthat August. The ollowing 12 projects

were selected rom 43 applications.

Dalla Park Fire Mitigation,LaPlata County, $24,800

Forest and Community WildreProtection Plan, Lake County, $69,000

Grand Junction Watershedand Fuel Reduction Program,

Mesa County, $140,000

Grand Lake Beetle Kill RemovalProject, Grand County, $140,000

Heil Valley Ranch 2008Fuels ReductionUnit 2,Boulder County, $50,000

Summary o 2009 Forest Legislation

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Horsetooth Mountain Park FuelsReduction, Larimer County, $80,000

Platte Canyon Fire/ForestRestoration and Water Protection

Project, Park County, $70,000

Santa Fe Trails Ranch Fuel BreakProject, Las Animas County, $125,000

Straight Creek Forest RestorationProject, Summit County, $10,895

Summit County HazardousFuels Reduction Project,Summit County, $140,000

Upper South Platte WatershedForest Health Initiative, Park

and Teller counties, $80,000

West Vail and Lower GoreCreek Fuel Reduction Project,Eagle County, $50,000

HB 07-1130 required only a

40-percent matching contribution;however, unds provided by thislegislation leveraged another $2.8

million in matching unds. All butone o the projects was completed by

April 30, 2009 (uncooperative weathercanceled Larimer Countys plans toburn slash piles, as saety to resources

and the community is non-negotiable).The 12 projects unded used a total

o $876,450 provided by the grant totreat 3,115 acres. The 12 communities

contributed an additional $1,355,004

in matching unds to accomplish theirrespective management objectives.

Since the advent o the pilot Forest

Restoration Program authorized

by HB07-1130, SB08-071 (SB 71)extended orest management eortsand continued community-based

approaches to orest restoration acrossColorados watersheds. Three severancetax increments provide $1 million

annually through 2012 to und orestrestoration projects. SB 71 is unding

$1.97 million or 29 projects scheduledor completion by September 2010.

Above: Beautiul highway vista near the San Juan Mountains. Photo: Katherine Timm.

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wilderness and range or livestock.Our orests require management and

protection to meet the needs o presentand uture generations o Coloradans

and the thousands o people who visitour state each year.

The level o insect and disease activitythat currently exists in Colorados

Forecasting the FutureWhat does the uture hold or Coloradosorests? Historical evidence suggests

that the presence o large numbers oless aggressive bark beetles, as seenin some o our lodgepole pine orestsin 2009, may signal the decline o thecurrent MPB epidemic. However, MPBactivity is increasing in ponderosa pineorests along the Front Range, whichhas suered major outbreaks in thepast. Te introduction o exotic pests,or those that are expanding their ranges(such as the walnut twig beetle), alsowill continue to pose a threat. Eectivemanagement o insect and disease

outbreaks and wildre will continue tochallenge resource management agenciesand private orest landowners.

All o the states orests, regardless o

ownership, provide a wealth o diversebenets clean water, recreation,

wildlie habitat, wood products,

the changes are continuous and subtleto the human eye. Whether the changes

are acceptable to us is a unction o ourvalues and needs. We have the ability

to shape our uture orests throughsound management to ensure they meet

individual and societal needs based onthe best available scientic inormation.

orests may be unprecedented, at least inrecent history. Changes in the structure

and composition o orests oten areimperceptible to humans, as we are only

present on the landscape or a portiono a orests lie cycle. As orests grow

and mature, the changes we observeseem to accelerate, although most o

Top: Elk bugling in Rocky Mountain National

Park. Above: Colorado columbines. Let: Western

tiger swallowtail (Papilio rutulus).Opposite: A

ponderosa pine orest restoration project on

the Upper South Platte. Photo: Jen Chase.

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Photo oForest

Management


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Reerences andFurther Reading

Agee, J.K., 1998. Fire and pineecosystems. In: Richardson, D.M.,Ecology and Biogeography o Pinus.Cambridge University Press , pp. 193-218.

Ciesla, W.M., 2009. Aerial oresthealth survey, portions o Colorado,

2009. Forest Health ManagementInternational, Fort Collins, Colo., 25 pp.

Ciesla, W.M., and E. Donaubauer,1994. Decline and dieback o treesand orests: A global overview. FAO,Rome, Italy, Forestry Paper 120, 90 pp.

Ciesla, W.M., and A.C. Mason, 2005.Disturbance events in Americasorests: An analysis o Criterion 3,Indicator 15 o the Montreal process Criteria and indicators o sustainable

orestry 2003. USDA ForestService, Forest Health echnologyEnterprise eam, Fort Collins, Colo.Report FHE-05 -02, 89 pp.

Ciesla, W.M., and I.R. Ragenovich,2008. Western tent caterpillar.USDA Forest Service, Forest Insectand Disease Leafet 119, 7 pp.

Ciesla, W.M., and J.J. Kruse,2009. Large aspen tortrix. USDAForest Service, Forest Insect andDisease Leafet 139, 8 pp.

Colorado Natural Heritage Program,2005. Biodiversity tracking andconservation system. ColoradoState University, Fort Collins, Colo.Southern Rocky Mountain Pinyon-Juniper Woodland, Revised September2005. http://www.cnhp.colostate.edu/

download/projects/eco_systems/pd/SRM_Pinyon-Juniper_Woodland.pd.

Colorado Natural Heritage Program,2005. Biodiversity tracking andconservation system. ColoradoState University, Fort Collins, Colo.Colorado Plateau Pinyon-JuniperWoodland, Revised September 2005.http://www.cnhp.colostate.edu/download/projects/eco_systems/pd/CP_Pinyon-Juniper_Woodland.pd.

Colorado State University, 2004. Insectsand diseases o woody plants in theCentral Rockies. Cooperative ExtensionService, Bulletin 506A, 292 pp.

Colorado State University, n.d.Pest alert: Walnut twig beetle andthousand cankers disease o blackwalnut. http://wci.colostate.edu/

36 Reerences
http://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdf


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Assets/pd/TousandCankers.pd. Site visited 19 August 2009.

DeRose, R.J., and J.N. Long,2009. Wildre and spruce beetleoutbreak: Simulation o interactingdisturbances in the Central RockyMountains. Ecoscience 16: 28-39.

Evenden. J.C., and A.L. Gibson, 1940.A destructive inestation in lodgepolepine stands by the mountain pinebeetle. Journal o Forestry 38: 271-275.

Furniss, R.L., and V.M. Carolin,1977. Western orest insects. USDAForest Service, MiscellaneousPublication 1339, 654 pp.

Graham, R.., echnical Editor,2003. Hayman Fire case study. USDAForest Service, Rocky Mountain

Research Station, General echnicalReport RMRS-GR-114., 396 pp.

Jahnke, J., 2009. Final one-year reporton HB071130, the Pi lot Forest

Restoration program. ColoradoDepartment o Natural Resources, 6 pp.

LeMaster, D.; Gouan Shao; andJ. Donnay, 2006. Protecting FrontRange watersheds rom highseverity wildre. Pinchot Instituteor Forest Conservation, 47 pp.

Lotan, J.E., and W.B. Critcheld,1990. Pinus contorta Dougl. exLoud., Lodgepole pine. In: R.M.Burns, and B.H. Honkanla. Silvics o

North America, Volume 1, Coniers.USDA Forest Service, AgricultureHandbook 654: 302-315.

Lynch, D. L., and K. H. Mackes, 2001.Wood use in Colorado at the turn othe twenty-rst century. Research PaperRMRS-RP-32. Fort Collins, Colo.: U.S.Department o Agriculture, ForestService, Rocky Mountain ResearchStation. 23 pp. Available online at http://www.s.ed.us/rm/pubs/rmrs_rp32.pd.

Lynch, H.J.; R.A. Renken; R.L.Crabtree; and P.R. Moorcra, 2006.Te infuence o previous mountainpine beetle (Dendroctomus ponderosae)activity on the 1988 YellowstoneFires. Ecosystems 9: 1318-1327.

Manion, P.D., 1991. reedisease concepts. Prentice HallInternational, 402 pp.

Mesa Verde National Park, n.d. Firehistory at Mesa Verde. http://www.

nps.gov.archive/meve/re/rehistory.htm. Accessed 20 November 2009.

Negrn, J.F.; J.J. Witcosky; R.J. Cain;J.R. LaBonte; D.A. Duerr II; S.J.McElwey; J.C. Lee; and S.J. Seybold,2005. Te banded elm bark beetle: Anew threat to elms in North America.American Entomologist 51: 84-94.

North American Plant ProtectionOrganization, 2008. Geosmithia spp. andPityophthorus juglandis. Beetle-ungus

inestation threatens black walnut(Juglans nigra) trees. http://www.pest.alert.org. Site visited 17 August 2009.

Oliver, W.W., and R.A. Ryker, 1990.

Pinus ponderosa Dougl. ex . Laws.Ponderosa pine. In: R.M. Burns,and B.H. Honkanla. Silvics oNorth America, Volume 1, Coniers.USDA Forest Service, AgricultureHandbook 654: 413-424.

Romme, W.H.; C.D. Allen; J.D.Bailey; W.L. Baker; B.. Bestelmeyer;P.M. Brown; K.S. Eisenhart; L.Floyd-Hanna; D.W. Human; B.F.Jacobs; R.F. Miller; E.H. Muldavin;.W. Swetnam; R.J. ausch; and P.J.

Weisberg, 2008. Historical and moderndisturbance regimes, stand structures,and landscape dynamics in pion-

juniper vegetation o the western U.S.Fort Collins, Colo.: Colorado ForestRestoration Institute, 35 p. Availableonline at http://warnercnr.colostate.edu/images/docs/cri/PJSynthesis.pd.

Smalley, J.C. (editor), 2003.Protecting lie and property romwildre. National Fire ProtectionAssociation, Quincy Mass., 388 pp.

Wood, S.L., 1982. Te bark andambrosia beetles o North and CentralAmerica (Coleoptera: Scolytidae), ataxonomic monograph. Great BasinNaturalist Memoirs 6, 1359 pp.

Worrel, J.J.; L. Egeland; . Eager; R.A.Mask; E.W. Johnson; P.A. Kemp; andW.D. Shepperd, 2008. Rapid mortalityoPopulus tremuloides in southwesternColorado, USA. Forest Ecologyand Management 255: 686-696.

USDA Forest Service 2004. Forestinsect and disease conditions inthe United States. Forest HealthProtection, Washington, D.C., 142 pp.

Photo: Ingrid Aguayo.

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Reerences
http://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://www.nps.gov.archive/meve/fire/firehistory.htmhttp://www.nps.gov.archive/meve/fire/firehistory.htmhttp://www.nps.gov.archive/meve/fire/firehistory.htmhttp://www.pest.alert.org/http://www.pest.alert.org/http://www.pest.alert.org/http://www.pest.alert.org/http://www.nps.gov.archive/meve/fire/firehistory.htmhttp://www.nps.gov.archive/meve/fire/firehistory.htmhttp://www.nps.gov.archive/meve/fire/firehistory.htmhttp://wci.colostate.edu/Assets/pdf/ThousandCankers.pdfhttp://

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