Bark Beetles in Utah - Cooperative Extension -

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Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory July 2012 ENT-165-12 Bark Beetles Ryan S. Davis, Arthropod Diagnostician, and Darren McAvoy, Extension Forestry Associate WHAT YOU SHOULD KNOW Bark beetles are a significant cause of tree mortality in the forest and urban environment. To protect high-value trees around homesites, use preventative trunk sprays of carbaryl, permethrin, and bifenthrin prior to beetle flight. Soil- and trunk-applied systemic insecticides (e.g., imidacloprid and dinotefuran) do not sufficiently protect trees from bark beetle attack. Fig. 2. Typical top-down dieback pattern on pines infested by Ips beetles 2 . Bark beetles are one of the most destructive forest pests in the world. They are different than the larger longhorned and roundheaded/metallic woodboring beetles commonly infesting the inner wood of trees. The largest bark beetle, the red turpentine beetle (Dendroctonus valens), reaches only 8.3 mm in length. Because of their tiny size (Fig. 1), bark beetles are not effective tree killers as individuals. Instead, primary bark beetles work together, sending pioneer beetles to search for stressed or dying trees. When pioneer beetles find a weakened tree, they bore into and feed BIOLOGY on the thin phloem layer just under the bark. As they feed, chemicals from their food are converted into attractive chemicals, signaling to other beetles of the same species that a suitable host was found. Beetles that detect the airborne chemicals will fly to the stressed tree, bore into the phloem, create a mating (nuptual) chamber, mate, and hollow-out a parental gallery laying eggs as they progress. Usually, many beetles attack the same tree in a short period of time allowing them to overcome its defenses (e.g., resin in pines). This is called mass attack. After egg hatch, immature beetles (larvae) (Fig. 12) begin feeding outward from the parental gallery, girdling the tree. This larval girdling is the same as killing a tree by deeply scoring its entire circumference with a knife or Fig. 1. Average size of an adult bark beetle compared to a penny 1 .

Transcript of Bark Beetles in Utah - Cooperative Extension -

Page 1: Bark Beetles in Utah - Cooperative Extension -

Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory July 2012ENT-165-12

Bark BeetlesRyan S. Davis, Arthropod Diagnostician, and Darren McAvoy, Extension Forestry Associate

WHAT YOU SHOULD KNOW• Barkbeetlesareasignificantcauseof

treemortalityintheforestandurbanenvironment.

• Toprotecthigh-valuetreesaroundhomesites,usepreventativetrunkspraysofcarbaryl,permethrin,andbifenthrinpriortobeetleflight.

• Soil-andtrunk-appliedsystemicinsecticides (e.g., imidacloprid and dinotefuran)donotsufficientlyprotecttreesfrombarkbeetleattack.

Fig. 2. Typical top-down dieback pattern on pines infestedbyIpsbeetles2.

Barkbeetlesareoneofthemostdestructiveforestpestsintheworld.Theyaredifferentthanthelargerlonghornedandroundheaded/metallicwoodboringbeetlescommonlyinfestingtheinnerwoodoftrees.Thelargestbarkbeetle,theredturpentinebeetle (Dendroctonus valens),reachesonly8.3mminlength.Becauseoftheirtinysize(Fig.1),barkbeetlesarenoteffectivetreekillersasindividuals.Instead,primarybarkbeetlesworktogether,sendingpioneerbeetlestosearchforstressed or dying trees. When pioneer beetles findaweakenedtree,theyboreintoandfeed

BIOLOGY

onthethinphloemlayerjustunderthebark.Astheyfeed,chemicalsfromtheirfoodareconverted into attractive chemicals, signaling tootherbeetlesofthesamespeciesthatasuitablehostwasfound. Beetles that detect the airborne chemicalswillflytothestressedtree,boreintothephloem,createamating(nuptual)chamber,mate,andhollow-outaparentalgallerylayingeggsastheyprogress.Usually,many beetles attack the same tree in a short periodoftimeallowingthemtoovercomeitsdefenses(e.g.,resininpines).Thisiscalledmassattack.Afteregghatch,immaturebeetles(larvae)(Fig.12)beginfeedingoutwardfromthe parental gallery, girdling the tree. This larval girdling is the same as killing a tree by deeply scoringitsentirecircumferencewithaknifeorFig.1.Averagesizeofanadultbarkbeetlecompared

to a penny1.

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HOW DO I KNOW IF MY TREES ARE INFESTED?

Fadingtreecrowns(Figs.3-4)aregoodindicatorsofbarkbeetleinfestationorotherhealthproblems.Insomecases,crownfadingcanbedelayedbycoldtemperatures.Treesattackedinfallmayremainmostlygreenuntilearlysummer.Crownfadingrangesfromveryslightoff-green,toyellow,brown,andred, depending on how recently the tree was attacked. Trees attacked by Ips beetles usuallyhavecrowndie-backfromthetopdown,whichmayhappenoverthecourseofaseasonorafewyearsassuccessivebeetlegenerations attack progressively lower portions ofthetree. Ifthecrownappearsoffcolored,completeathoroughinspectionofthetreetrunkandbranches.Lookforasawdustlikesubstance(frass)thatcanbefoundinthecracksandcrevicesoftreebarkoronthegroundaroundthetrunk(Fig.5).Alsolookforpitchtubes(Figs.6-8),whichareresindepositsexudedfromtreesinanattempttodefenditself.Pitchtubesaremostcommononpinetrees,butsmallamountsofpitchfromsomehardwoods may also be seen. The presence ofpitchtubesand/orfrassindicatestheneedforfurtherinvestigation.Ifthetubesand/orfrassarevisibleonmorethanhalfofthetrunkcircumference,useahatchettopullbackbarkfromanareaunderthepitchtubesandexaminetheexposedwoodandbackofbark. Lookforsignsofcurrentorpastbeetleinfestationssuchasgalleries(Fig.10),eggs,larvae(Fig.12),pupae,andadultbeetles.Ifgalleries and larvae are present, this indicates acurrentattack.Ifthegalleriesareemptyandnolarvae,pupaeoradultbeetlesarepresent,thentheinfestationislikelyold.Notethatsomebeetles,suchasthewesternpinebeetle,will

saw.Oncethephloemlayerisgirdled,nutrienttransport within the tree stops, and the tree eventuallydies.Manybarkbeetlescarryafungusthatinhibitswatertransportwithinthetree, aiding in tree death. Inanurbansetting,treesareeasilystressedbyheatanddrought,soilcompaction,over/underwatering,oldage,and mechanical damage making them prime targetsforbarkbeetles.Ourhabitofplantingidenticaltreespeciesingroupsorrowsmakesthe problem worse, allowing beetles to easily move between closely growing host trees and causemajoraestheticdamage.

Fig.3.Recentlyinfestedtreesmaynotshowobvioussignsoffading3.

Figs.4-5.(Left)Fadingcrownofbarkbeetleinfestedtrees2.(Right)

Frass,orsawdust-likematerialonthetrunkisinindicationofbarkbeetle

infestation4.

Figs.6-8.(LeftandRight)Pitchtubesaredefensivechemicalcompounds

exudedfromthetreethatmayindicatebarkbeetleattack5,6.(Upperleft

corner)Barkbeetlecaughtbyatree’sdefensiveresin7.

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BEETLE IDENTIFICATION AND COMMON UTAH BARK BEETLES

Bark beetles are small and similar looking.Alwayshaveyourbeetleidentifiedbyaprofessionalentomologist.However,homeowners can narrow down the possibilities byansweringthefollowingquestions:

1)Whattreespeciesisaffected?UseTable1onthefollowingpagetonarrowdownpossiblebarkbeetlesusinghostplant/treeinformation.

2)Whatdothegallerieslooklike?Toviewgalleries,barkmustberemovedfromthetree.Donotattemptthisunlessyouaresurethewholetree,orthepartofthetreeyouareinterestedinisdead.Lookatthegallerypicturesbelowandmatchthemwiththegeneralshapeofyourgalleries.

3)Whatisthegeneralappearanceofthebeetle?Lookattheadultbeetlepicturesbelowandmatchmajorfeatures.Beetlesareextractedfromthetreeusingdestructivehatchet sampling methods as well.

entertheouterbarklayersinlaterlarvalstages.Iftheconditionofthephloemlayer(soft,white,thinlayerbetweenthebarkandwoodlayers)isbrowntoblack,orcompletelydried-up,thenthetreemaybedead.Checktherestofthecircumferenceofthetreeforlivephloem.Ifnolivingphloemisfound,thetreeshouldberemoved and treated to kill the beetles; see the“Sanitation”sectionfortechniques. Beetleexitholesoftenhavea“shotgun”patternintreebark(Figs.9&11),indicatingthat bark beetles have already exited the tree. Ifyouseeanysignsofbarkbeetles--fadingcrown,pitchtubes,frass,galleries(Fig.10),larvae(Fig.12),oradults--besuretoexaminetherestofthetreesonyourpropertyforsignsofbeetleattack,especiallytreesofthesameorrelatedspecies.Ifyouliveclosetoyourneighbors,theyshouldalsobenotifiedtoexaminetheirtrees.Ifyouarenotcomfortableevaluatingyourowntree,contactaqualifiedarboristforhelp,orsubmitsamplestotheUPPDL.

Fig.9.Exitholescreatedfromemergingadultbarkbeetles8.

Figs.10-11.(Left)Barkbeetleparentalandlarvalgalleries;larvaecanbe

seeninnewlyconstructedpupalchamberswheretheywilltransforminto

adults9.(Right)Shotgunpatternofexitholesfromshotholeborers6.

Fig.12.Barkbeetlelarvaeareleglesswhitegrubswithabrownhead

capsule10.

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Utah’s Common Bark BeetlesBark Beetle Name Scientific Name Utah Hosts Generations

Per Year*

SpruceIps Ips hunteri blue&Engelmannspruce 2 - 3

SpruceIps Ips pillifrons Engelmannspruce 2 - 3

PineEngraver Ips piniponderosa, lodgepole, and occasionally other

pines2 - 3

PinyonIps Ips confusus pinyonandsingleleafpinyon upto5

Six-SpinedIps Ips calligraphus ponderosa pine 2 - 4

Pine“Ips” Orthotomicus latidenspinyon, lodgepole,

limber, ponderosa and other pines

1 - 2

Banded Elm Bark Beetle Scolytus schevyrewi elms 2 - 3

EuropeanElmBarkBeetle Scolytus multistriatus elms 2 - 3

Fir Engraver Scolytus ventralis firs 1/2-1

Shot-hole Borer Scolytus rugulosus apples, pears, cherries, and hawthorns 2

MountainPineBeetle

Dendroctonus ponderosae

lodgepole, ponderosa, limber, and other pines 1

Douglas-FirBeetle Dendroctonus pseudotsugae Douglas-fir 1

RoundheadedPineBeetle Dendroctonus adjunctus ponderosa pine 1

SpruceBeetle Dendroctonus rufipennis Engelmannandbluespruce 1/2-1

EuropeanShot-hole Borer Xyleborus dispar

Norway&sugarmaple,water & paper birch, hazels,walnuts,apples,

pears, cherries, oak, willow, and grapes

1

WalnutTwigBeetle Pityophthorus juglandis walnuts 2

ArizonaCypressBeetle Phloeosinus cristatus

Arizonacypress,junipers,cedars,sequoia,

redwood1 - 2

Western balsam Engraver Dryocetes confusus

sub-alpinefir,whitefir,andEngelmannspruce

(notcommon)1/2

Table1.CommonbarkbeetlesandhosttreesinUtah.*Generationsperyeararegiven,butmayvarydependingonyourlocationinUtah:uselowerestimates

fornorthernUtahandhighelevationsandthehigherendforsouthernandlowerelevationsites.

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DENDROCTONUS BEETLES

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IPS BEETLES

Ipsbeetlesarethemostcommonlyencounteredbarkbeetlesinlandscapepines.Adultbeetles(topleftandright)havespinesalongtheirouterwings.Ipsgalleriesresembletheshapeofanoctopusbutwithfewerarms.Thereisacenterchambergivingrisetomultipleparentalgallerieswhereeggsarelaid.Uponhatching,larvaeradiateoutwardfromtheparentalgallery.Larvalgalleriesbecome progressively wider as the larvae grow, terminating in acirculartoovalpupalchamber.Ideally,adultsandimmaturebeetleswillbepresentinyoursample,indicatingtheyarestillinthetree.Ifemptygalleriesandpupalchambersarepresentthenit is likely the beetles have emerged to attack another host.

BarkbeetlesinthegenusDendroctonusaresomeofthemostdevastatingforestinsectpestsintheworld.Themostnotablespeciesinthewestisthemountainpinebeetle(MPB),responsibleforthedestructionofmillionsofacresoftimbereveryyear.Mountainpinebeetlelessfrequentlyattackspinetreesinthenon-forestedurbanlandscape.MPBgalleiesarerecognizedaslong,straight,verticalgallerieswitha“j”crookatthebottom.Thegalleriesusuallyextendfrom1to3feetupthetree.OtherDendroctonus species affectanarrowerrangeofhosttrees.ThesewillbemostcommonlyseeninhighelevationlodgepoleandspruceforestsinUtah.

Figs.12.-14.(Left)Ipsbarkbeetlehaveobviousspinesontherearoftheirouterwingsanda(Center)

concave depression11-12. Ipsgalleriescanbeidentifiedbyacentralnuptualchamber(Right)with

parentalgalleriesradiatingoutwardgivingan“octopus”shape13.

Figs.15.-17.(Left)AdultmountainpineissimilarinappearancetootherDendroctonus bark

beetles14. Dendroctonusbeetlegalleriesvaryfromspaghetti-platepatternsofparentaland

larvalgalleries(Center)tolongandstraightparentalgallerieswithoutwardradiatinglarval

galleries(Right)8-15.

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SCOLYTUS BEETLES

DRYOCETES, PHLOEOSINUS, PITYOPHTHORUS, AND XYLEBORUS BEETLES

OfthefourcommonScolytus beetles in Utah, the elm-feedingEuropeanelmbarkbeetleandthebandedelmbarkbeetlearethemostabundantintheurbanlandscape.TheyarealsomajorvectorsoftheDutchElmDisease(DED)fungus,whichcankillelmtreesorcausechronicillnessandstress.Formorein-depthinformation,pleaseseeourfactsheet“Elm Bark BeetlesandDutchElmDisease.” Theshotholeborercaninfeststressedorinjuredportionsofapple,cherry,pear,andhawthorntreesinUtah.Normally,thisbeetlekillslargertreebranchesratherthanwholetrees.InUtahthefirengraverbeetlecommonlykillsstressedfirtreesinhigh-elevationforests,butcaninfestfirtreescommonlyplantedin the landscape.

ThebeetlesinFigures24-27aremostlyminorpestsinUtah.Thewesternbalsambarkbeetlemostlyattackdiseasedorstressedfirtreesathighelevations,butcouldaffectwhiteandotherornamentalfirsinthelandscape.AllrecordsofPhloeosinusbeetlesinUtaharefromornamentalArizonacypresstreesinWashingtonCounty. Most Pityophthorusbeetlesaffectsmallerlimbsandbranchesondyingorstressedtreesorlimbs.Theyusuallydonotcausetreedeathandarenotapestofconcern.OnenotableexceptionistheWalnutTwigBeetle,whichtogetherwithitstree-killingfungus,ThousandCankersDisease(Geosmithia sp.),haskilledmanyblackandotherwalnutsthroughoutthewestandareasofthemidwestandsoutheast.Together,thebeetleandfungusarethemajorpestofwalnutsintheU.S.FormoreinformationonthisbeetlereadthefactsheetfromColoradoStateUniversity. Xyleborusbeetlesarecalledambrosiabeetlesbecauseoftheambrosiafungustheycarry.Ambrosiabeetlesaredifferentfromotherbarkbeetlesinthattheydonotfeedinthephloemlayer,butboreintothesapwoodofthetree.Onceinthesapwood,theyfeedonthegrowingambrosiafungusinsideoftheirgalleriesfromwhichtheygaintheirnutrition.

Figs.18-20.(Left)Firengravergalleries1.(Middle)Bandedelmbarkbeetlefeedingonbranchcrotches16.(Right)Shotholeboreradult1.

Figs.21-23.(Left)Adultwesternbalsambarkbeetle15.(Middle)AdultPhloeosinus beetle18.(Right)Adultwalnuttwigbeetle19.

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CONTROLMechanical/Physical: Keeptreeshealthyandstressfreewithproperdeepwateringandfertilization,especiallyforold,stressedtrees.Insomesituations,treerootsmustcompetewithturfroots or will have deeper root systems than turfandmustbewateredlessfrequentlyforlongerdurations.Soilshouldcontainadequatemoisturetoadepthofabout20inches.Soilmoisturecanbetestedbypushingalongscrew driver or slim metal rod into the soil. The metal will easily penetrate moist soil, and will stop when dry soil is reached. Deep watering totreesshouldbedoneonceaweekduringhotsummermonths(July,August)andlessfrequentlyinthecoolermonths.Theamountofwaterittakestodeepirrigateto20incheswilldependonyoursoiltype(lesswaterforsandysoils,moreforclaysoils),soexperimentwithwateringtimesuntilyourscrewdrivertestshowsmoisturetoadepthofabout20inches.Irrigationatnormalturfvolumesisnotadequatefortreeirrigation.Supplementaloradditional sprinkler irrigation is necessary. For moreinformationonproperwateringclick here. Barkbeetlecontrolmustbepreventativeandshouldbeginwithmonitoringandscouting.Closelyobserveyourtreestocatchhealthissuesbeforetheybecomemajor problems. For more detail on what to lookfor,seethesection“HowdoIKnowifMyTreeisInfested?”above.ConsultyourlocalUSUExtensionofficeortheUPPDLforcurrentinformationonbeetleflightsandspraytiming.

Monitoring/Traps: Lindgrenfunneltrapsusedincombinationwithattractivelures(e.g.,ipstrilure,alpha-pinene,ethanol,etc.)canattractvariousbarkbeetles.Whenbeetlesspecifictoyourhosttree(e.g.,spruceipsandbluespruce)beginshowingupintraps,preventativespraysshouldbeappliedimmediately.Whiletrapscangiveaccurateadultflightinformation,theyalsoattractbeetlestoyourproperty,whichcouldleadtotreeattack.Usetrapsandlurescarefully.Neverlocate traps near host trees as spillover can occur.Itismoreeffectivetovisuallymonitoryourneighborhoodandsurroundingareastoseeiftreeshavebeenkilledbybarkbeetles.Thiscouldindicatethatbeetlesareinthearea,andthatprotectionofhigh-valuetreesmaybeneeded.

Chemical Control: Oncethebeetlesareunderthebarkand have girdled the tree, there are no chemicalsthatwillsavethetree.Preventiveinsecticidesshouldbeappliedbeforebeetlesemergeinspringorearlysummer.Springinsecticideapplicationsshouldoccuroncetemperaturesareconsistentlyover50°F.Atthistemperature,manybarkbeetlescontinuedevelopmentunderthebarkoremergetofindnewhosttrees.Properlytimedandapplied insecticides will kill bark beetles as they chewthroughtheinsecticide-soakedbark,preventingsuccessfulattack.Someproductsarelabeledfortrunkapplicationstoinfestedtreestokillbeetlesastheyemergeorunderthebarktopreventinfestationofadditionaltrees. To date, no systemic insecticides have beenproveneffectiveatpreventingbarkbeetlesfromkillingtrees. Toprotectornamental(non-fruitbearing)treesfrombarkbeetleattackapplya preventative insecticide prior to beetle flight.Sincebarktreatmentsareappliedatahigherratethanforothersites,selectproductslabeledforuseasabarktreatmentonornamentalorforesttrees,dependingonyoursituation.Themosteffectiveactiveingredientsincludecarbaryl,bifenthrin,andpermethrin.Belowareafewexamplesofeach.Linkstoproductlabelsareincluded,butmaybeoutdated.Pleasemakesureyoureadthelabelontheproductyoupurchasebeforeuse.Informationonbarkbeetleprevention/controlcanbefoundnearthebottomoftheproductlabels.

Carbaryl: Group 1A, Carbamates +Carbaryl4L(label) - Type: Generaluse.

- Site: Directtrunktreatment:Roses,flowers,otherherbaceous plants,woodyplants,evergreens,andshrubs.

- Labeled Pests: Elmbarkbeetle,Ipsengraverbeetles,mountain pinebeetle,roundheadedpinebeetle,sprucebeetle, western pine beetle.

- Application: Applytobarkandmainbranchesdownto5 inchesdiameterinspringpriortoflight.Onlyoneapplication per year needed.

- Notes: Licensedprofessionalwithhigh-poweredspray equipmentrecommended.Quantitiessoldintendedfor agriculturalorcommercialuse.

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+SevinXLRPlus(label) - Type: Generaluse.

- Site: Directtrunktreatment:Forestedareasandrangeland trees;forests,treeplantationsplantedChristmastrees,parks, ruralshelterbelts,rangelandtrees.

- Labeled Pests: Elmbarkbeetle,Ipsengraverbeetles, mountainpinebeetle,roundheadedpinebeetle,spruce beetle, western pine beetle.

- Application: Applytobarkandmainbranchesdownto5 inchesdiameterinspringpriortoflight.Onlyoneapplication per year needed.

- Notes: Licensedprofessionalwithhigh-poweredspray equipmentrecommended.Quantitiessoldintendedfor agriculturalorcommercialuse.

Bifenthrin: Group 3A, Pyrethroids

+BifenXTSInsecticide/Termiticide(label) - Type: Generaluse.

- Site: Trunkspraytoornamentaltrees.

- Labeled Pests: To control Dendroctonusbarkbeetlessuchas blackturpentinebeetle,mountainpinebeetle,westernpine tipbeetle,southernpinetipbeetle,andengraverbeetles (Ipsspp.)Alsoforuseonotherbarkbeetlessuchas ambrosia beetles, elm bark beetles, and emerald ash borer.

- Application: Applytobarkandmainbranchesdownto5 inchesdiameterinspringpriortoflight.Onlyoneapplication peryearneeded.Canalsobeusedtocontrolemerging broodfromattackedordeadtrees.

- Notes: Licensedprofessionalwithhigh-poweredspray equipmentrecommended.Recommendedforlicensed commercialapplicatorsfortermitecontrol,butincludes applicationtoornamentaltreesforthecontrolofbark beetles.

+OnyxInsecticide(label) - Type: Generaluse.

- Site: Trunkspraytoornamentaltrees.

- Labeled Pests: To control Dendroctonusbarkbeetlessuchas mountainpinebeetle,southernpinebeetle,westernpine beetle,blackturpentinebeetle,andengraverbeetles(Ips spp.)Alsoforuseonotherbarkbeetlessuchasambrosia beetles, elm bark beetles, and emerald ash borer.

- Application: Applytobarkandmainbranchesdownto5 inchesdiameterinspringpriortoflight.Onlyoneapplication peryearneeded.Canalsobeusedtocontrolemerging broodfromattackedordeadtrees.

- Notes: Licensedprofessionalwithhigh-poweredspray equipmentrecommended.Intendedforusebylicensed commercialapplicatorsforcontrolofturfandornamental pests.

Permethrin: Group 3A, Pyrethroids+ Astro (label) - Type: Generaluse.

- Site: Ornamental trees.

- Labeled Pests: Tocontrolbarkbeetles:Dendroctonus spp., Ips spp.,elmbarkbeetles,mountainpinebeetle,pine engravers,turpentinebeetles,andwesternpinebeetle.

- Application: Applytobarkandmainbranchesdownto5 inchesdiameterinspringpriortoflight.Canalsobeusedto controlemergingbroodfromattackedordeadtrees.

- Notes: Licensedprofessionalwithhigh-poweredspray equipmentrecommended.Intendedforusebylicensed commercialapplicatorsforcontrolofinsectpestsonlawns, ornamentaltreesandshrubsandaroundbuildingsfor perimeterinsectcontrolincludinglandscapedareas aroundresidential,institutional,public,commercialand industrialbuildings,parks,recreationalareas,andathletic fields.

+HiYield38PlusTurf,Termite&Ornamental InsectControl(label) - Type: Generaluse.Intendedforhomeowneruse.

- Site: Ornamentals.

- Labeled Pests: To control bark beetles and boring insects (including,butnotlimitedto:ashborer,bronzebirchborer, rhododendronborer,elmbarkbeetlesandturpentine beetles.)

- Application: Stem-infestingbeetles:treatlowerbranchesand trunkpriortoadultemergence.Complete,uniform coverageisneededforbestcontrol.Arepeatapplication may be necessary on a 3 to 4 week interval to prevent severe tree stem damage.

- Notes: Foroutdoorhomeowner(residential)useonly.Best productforusebynon-licensedchemicalapplicators.High poweredsprayequipmentneededforcompletecoverage on larger trees.

Forhomeowners,Hi-Yield38PlusTurf,Termite&OrnamentalInsectControlContaining38%Permethrinisreadilyavailable,soldinvariousquantities,reasonablypriced,andcanbeusedforotherresidentialturfandlandscapepests.Othergeneraluseproductsabovecanbepurchasedforhomeowneruse,butusuallycomeinlargerquantitiesandareintendedforusebylicensed,commercialapplicators. Applicationofchemicalstakesspecialequipment.Iflargertreesneedtreatment,hireacompanywithhigh-pressuresprayequipmenttoreachfarupinthetreeforcompletecoverageandoptimumprotection.Selectaproductthatislabeledfortheintendedsiteandsituationofapplication.

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UtahStateUniversityiscommittedtoprovidinganenvironmentfreefromharassmentandotherformsofillegaldiscriminationbasedonrace,color,religion,sex,nationalorigin,age(40andolder),dis-ability,andveteran’sstatus.USU’spolicyalsoprohibitsdiscriminationonthebasisofsexualorientationinemploymentandacademicrelatedpracticesanddecisions.UtahStateUniversityemployeesandstudentscannot,becauseofrace,color,religion,sex,nationalorigin,age,disability,orveteran’sstatus,refusetohire;discharge;promote;demote;terminate;discriminateincompensation;ordiscriminateregardingterms,privileges,orconditionsofemployment,againstanypersonotherwisequalified.Employeesandstudentsalsocannotdiscriminateintheclassroom,residencehalls,orinon/offcampus,USU-sponsoredeventsandactivities.ThispublicationisissuedinfurtheranceofCooperativeExtensionwork,actsofMay8andJune30,1914,incooperationwiththeU.S.Dept.ofAg.,NoelleE.Cockett,VicePresidentforExtensionandAgriculture,UtahStateUniversity.

Page9UPPDL,5305OldMainHill,LoganUT84322,utahpests.usu.edu T:435.797.2435F:435.797.8197

Precautionary Statement:UtahStateUniversityExtensionanditsemployeesarenotresponsiblefortheuse,misuse,ordamagecausedbyapplicationormisapplicationofproductsorinformationmentionedinthisdocument.Allpesticidesarelabeledwithingredients,instructions,andrisks,andnotallareregisteredforediblecrops.“Registereduse”pesticidesmayonlybeappliedbyalicensedapplicator.Thepesticideapplicatorislegallyresponsibleforproperuse.USUmakesnoendorsementoftheproductslistedherein.

PHOTOS

Avoiduseofthesechemicalsonfloweringtreesduringbloomtopreventbeedeath.Forfullprotection,applytheproductofchoicethroughoutthegrowingseasonattheintervallistedonthelabel.Someoftheproductsaboveonlyrequireoneapplicationperyearinthespringpriortobeetleflight.ContactyourlocalExtensionofficeortheUPPDLforguidanceonspraytimingandproductselection.

Sanitation: Ifanactiveinfestationisdiscoveredinatreeandthetreewilldie,thetreeshouldberemoved immediately and treated to prevent furtherdevelopmentandflightofbeetles.Acommon mistakeistocutdownaninfestedtreeandthenstackinfestedlogsundera

1USDAForestService,OgdenArchives,Bugwood.org.2WilliamM.Ciesla,ForestHealthInternational,Bugwood.org3BillCiesla,ColoradoStateUniversity.4BryttenSteed,USDAForestService,Bugwood.org.5ChrisSchnepf,UniversityofIdaho,Bugwood.org.6JackKellyClark,UniversityofCaliforniaStatewideIPMProject.7DarrenBlackford,USDAForestService,Bugwood.org.8RonaldFBillings,TexasForestService,Bugwood.org.9LaddLivingston,IdahoDepartmentoflands,Bugwood.org.10GeraldJ.Lenhard,LousianaStateUniversity,Bugwood.org.11PestandDiseaseImageLibrary,Australia,Bugwood.org.12DavidT.Almquist,UniversityofFlorida,Bugwood.org.13JeraldDewey,USDAForestService,Bugwood.org.14ErichG.Vallery,USDAForestService,Bugwood.org.15USDAForestService,Region2,Bugwood.org.16WhitneyCranshaw,ColoradoStateUniversity,Bugwood.org.17BudapestHorvathMuseum,Victoria,Melbourne,Australia,Bugwood.org.18NatashaWright,FloridaDeptmentofAg.andConsumerServices,Bugwood.org.19JimLabonte,OregonDepartmentofAgriculture.

ADDITIONAL RESOURCESIpsBeetles:ColoradoStateUniversityFactSheetMountainPineBeetle:ColoradoStateUniversityFactSheetUSDA Forest Service, Rocky Mt. Research Station WebsiteUtahDivisionofForestry,FireandStateLandsFactSheetUniversityofCaliforniaIntegratedPestManagementProgramFactSheetBarkandWoodboringBeetlesoftheWorldWebsite

nearby host tree. Removing a tree does not kill thebeetlesandtheycanstilldevelopunderthe bark and emerge to attack more trees! Aftercuttinganinfestedtreetherearemultipletechniquesforkillingbeetlesunderthebark: - Debark: Removeallbarkfromthetree.

- Insecticide Spray: Use a labeled insecticide to treat the tree priortoremovalortologsafterremoval.

- Solarization: Cutlogsintendedforfirewooduseshouldbe stackedinanareaoffullsunandcoveredtightlywithblack plastic.

- Suffocation: Logscanbeburiedundersoilorsubmergedin water.

- Chip: Ifnofirewoodisdesired,cutlogscanbechippedand usedasmulch.

FactSheetSeries:Insects-LandscapeandOrnamental