Dogwood Borer, permaculture
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Insects
Extension
SP290-C
Dogwood Borer
Infestation, Damage and Control
Frank A. Hale, Professor
originally developed by Harry E. Williams, Professor Emeritus
Entomology and Plant Pathology
Theloweringdogwood(
Cornus
lorida
)isoneofthemostpopular
ornamentalplantsinTennesseelandscapes.
Nativetreesalsolourishintheforest
understory.
Thedogwoodtreeisdamagedbythe
feedingactivityofthedogwoodborerlarva
underthebarkofthetrunkandlimbs.In
asingleyear,oneborercancompletely
girdleandkillatree4inchesindiameter,
butdeathismoreoftenbroughtaboutby
thecombinedactivityofseverallarvaeor
bysuccessiveinfestationswithconcurrent
mechanicalinjuryorpathological
problems.Cultivatedtreesgrowinginfull
sunareusuallymoreheavilyinfestedthanthosegrowing
inshadedorforestedareas.
Thedogwoodborer,
Synanthedon scitula
(Harris),
isfoundthroughouttheareawherelowering
dogwoodsaregrown.Inadditiontodogwoods,the
boreralsoinfestsoak,chestnut,elm,hickory,willow,
pecanandapple.Theborerinfestsawiderangeof
hostplants,anddogwoodtreesmaybeinfestedfrom
avarietyofnearbyhostplants.Anative
pest,theborerisknownbyseveralother
commonnames:pecansesia,nine-bark
borer,woodygallborer,oakgallborerand
others.
AdultmothsemergefromlateAprilto
mid-October,withtheirstpeakofadult
activityoccurringinmid-Mayandthe
secondpeakinearlyAugust.Eggsarelaid
singlyonthebark.Whenirstlaid,theegg
ispaleyellowandturnsonlyslightlydarker
beforethelarvahatches.Thefemalemay
laymorethan100eggsthatusuallyrequire
eighttoninedaystohatch.
Newlyhatchedlarvaeenterthrough
wounds,callousedareas,cankersorsomebrokenbark
site.Larvalfeedingisconinedtotheinnercambiumand
bark.Thedogwoodborerhibernatesinthelarvalstage
withinitstunnel.Pupationtakesplacethefollowing
season.Althoughthereisonlyonegenerationperyear,
borersmaybefoundinvariousstagesofdevelopment
throughoutmostoftheyearbecauseeggsarelaidovera
periodofseveralmonths.
Dogwood borer damage
John A. Weidhass, Virginia
Polytechnic Institute and State
University, www.forestryimages.org
Themothpassesthroughfourseparate
stagesinitslifecycle(egg,larva,pupaand
adult).Thebasiccoloroftheadultmoth
isdarkblue,appearingalmostblack,with
occasionalyellowmarkingsonthebody.
Thedarkthoraxismarkedwithyellowlines
andayellowpatchbelow.Theabdomenis
darkwithyellowonthesecondandfourth
segments.Thewingsaremostlyclearwith
darkscalesalongtheveinsandmargins
andaspanofaboutthree-ifthsofaninch.
Dogwoodborermothsareinthesame
familyofclearwingmoths(
sesiidae
)asthe
peachtreeborer,rhododendronborerand
thelilacborer.
Thelarvaeareoff-whitetocream-
coloredwithareddish-brownhead.The
frontthoracicsegmenthastworeddish-brownspots
ontheuppersurface.Thenewlyhatchedlarvaeare
1/16ofaninch,andthematurelarvaeare3/5ofan
inchlong.Thepupaearelightbrownand2/5ofan
inchlong.
thathavebeenpreviouslyinfestedhave
woundsthatprovideeasyentryforborers.
Avoidphysicaldamagetothetrees.
Spraythetrunkandlowerlimbscaffold
withtherecommendedinsecticideinlate
Aprilandmid-Julyforfull-seasoncontrol.
Applytheinsecticidefromthelower
limbscaffold,downthetrunktothesoil
line.Landscapetreescanbetreatedwith
bifenthrin(Onyx)orpermethrin(Astro,
PermethrinPro).Usepermethrin(Perm-
Up3.2EC)orchlorpyrifos(Dursban)for
dogwoodborercontrolincommercial
nurseries.
Ifaprotectiveinsecticidesprayisnot
used,aparasiticnematode,
Steinernema
carpocapsae
(Guardian),canbeappliedto
theinfestedtreetruckasacoarse,low-pressurespray
tothepointofrunoff.MakeapplicationsduringMay
throughSeptemberwhensignsoflarvaeareapparent.
Adult male
James Solomon, USDA Forest
Service, www.forestryimages.org
References
Pless,C.DandW.W.Stanley.1967.Lifehistoryand
habitsofthedogwoodborer,
Thamnosphecia scitula
(Lepidoptera:Aegeriidae)inTennessee.Journalofthe
TennesseeAcademyofScience.42(4):117-123.
Control Measures
Dogwoodtreesmaybeinfestedinanurseryas1-,
2-or3-year-oldseedlingsorasoldertreesgrowingin
thelandscape.Treesshouldbeinspectedfordepressed,
wetorlooseareasofbarkindicatingpossibleborer
infestationpriortopurchase.
Physicaldamagetothebarkofthetrunkorlimbs
fromlawnmowers,stringtrimmers,dogwoodcanker,
pruningcutsorfreezingthebarkaidborerentry.Trees
Rogers,L.E.andJ.F.Grant.1990.Occurrenceof
dogwoodborerandotherselectedspeciesofclearwing
borerinEasternandMiddleTennessee.Tennessee
FarmandHomeScience.Issue154.TheUniversityof
TennesseeAgriculturalExperimentStation,Knoxville.
Precautionary Statement
Toprotectpeopleandtheenvironment,pesticidesshouldbeusedsafely.Thisiseveryone’sresponsibility,especiallytheuser.
Readandfollowlabeldirectionscarefullybeforeyoubuy,mix,apply,storeordisposeofapesticide.Accordingtolawsregulating
pesticides,theymustbeusedonlyasdirectedbythelabel.Personswhodonotobeythelawwillbesubjecttopenalties.
Disclaimer Statement
Thispublicationcontainspesticiderecommendationsthataresubjecttochangeatanytime.Therecommendationsinthispublication
areprovidedonlyasaguide.Itisalwaysthepesticideapplicator’sresponsibility,bylaw,toreadandfollowallcurrentlabeldirections
forthespeciicpesticidebeingused.Thelabelalwaystakesprecedenceovertherecommendationsfoundinthispublication.
Useoftradeorbrandnamesinthispublicationisforclarityandinformation;itdoesnotimplyapprovaloftheproducttothe
exclusionofothersthatmaybeofsimilar,suitablecomposition,nordoesitguaranteeorwarrantthestandardoftheproduct.The
author(s),theUniversityofTennesseeInstituteofAgricultureandUniversityofTennesseeExtensionassumenoliabilityresulting
fromtheuseoftheserecommendations.
SP290C 06-0248
Programs in agriculture and natural resources, 4-H youth development, family and consumer sciences, and resource development.
University of Tennessee Institute of Agriculture, U.S. Department of Agriculture and county governments cooperating.
UT Extension provides equal opportunities in programs and employment.
Adult female
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