Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory December 2011ENT-052-11

Bumble Flower BeetleTaun Beddes, Cache County Horticulture Agent, and Ryan S. Davis, Arthropod Diagnostician

DO YOU KNOW?• Bumbleflowerbeetlesarecommonthroughoutthe

growingseasononflowers,oozingsap,andothersweet,overripe,orfermentingmatter.

• Bumbleflowerbeetlesseldomwarranttheuseofchemicalsforcontrol.

• Control methods include removing organic materialfromnearaffectedplants,andhandremovaloftheadultbeetlesfromplants.

INTRODUCTIONFig.2.Adultbumbleflowerbeetle(Euphoria inda)2.

Bumble Flower BeetleScientific Name: Euphoria inda(Scarabaeidae)

Range: WidelydistributedintheUnitedStatesfromConnecticuttoFloridaandwestwardtoOregonandArizona.

Hosts: Identification Adult: AdultBFB’s(Fig.2)are12-16mm(7/16-5/8inch)inlengthand8-10mm(5/16-3/8inch)wide.Theyhaveyellowish-brownorcinnamon-coloredouterwingswithirregularrowsofsmallblackspots,manyofwhichmayberectangular.Theheadandthorax(sectionbehindhead)aredenselyhairy,asistheundersideofthebody,thelatterbeingclothedwithnumerouswhitehairs.Legsareareddish-browncolor.Whencaptured,adultsmayemitadefensivechemicalwithapungentchlorine-likeodor.

Identification Immature: cream-coloredgrubwithadarkbrownheadcapsuleanddarkgrayterminalbodysegment(Fig.1).Larvaehavesixlegsandareeasilymistakenforotherscarabbeetlelarvae,orwhitegrubs.

Life History: Overwinteringadultbeetlesbecomeactiveduringthefirstwarmdaysofspringandlayeggs.InUtah,BFB’shavebeenobservedfromearlyMaythroughlateSeptember.Afterhatching,larvaedevelopinsoilorothersubstratescontainingalargeamountoforganicmatter.Suchareasincludetheedgesofoldhayorstrawstacks,soilcontainingdecayingvegetationor

GENERAL BIOLOGY

Thebumbleflowerbeetle(BFB)isacommonmemberoftheScarabaeidae(scarab)beetlefamily.ItscommonnameoriginatedbecauseadultBFB’softenflyclosetothegroundandemitaloudbuzzingsoundsimilartothatofabumblebee.Larvae(grubs)andadultsareoftenfoundinornearfermentingand/ordecomposingorganicmatter.BecauseBFB’sfeedonandfurtherbreakdownorganicmattertheyarebeneficialinmanysituations.Economic damage caused by BFB in Utah is rare and theyseldomrequirecontrol,thoughlarvae(Fig.1)maybemistakenforotherdamagingpestssuchasJapanesebeetleandvariouslawnfeedingwhitegrubs.

Fig.1.Immaturebumbleflowerbeetle(Euphoria sp.)1.

manure,rottenwood,humus,orevenpottingsoil.Theymaybeabundantinareaswherespoiledvegetablesaredumped.ThenewgenerationmaturesandpupatesinJuly.Pupaemaybefoundinsoilatadepthof2to5inchesinsideovalearthencellsconstructedbythelarvae.InUtah,adultsofthenewgenerationemergeandbecomeactiveinmid-AugustthroughabouttheendofSeptember,andthentheyseekaplacetooverwinter.Thereisonegenerationperyear.

Key Habits/Damage Description: Adult BFB’s are reported toinjurecorninthesilkstage,althoughthisproblemisseldom reported. Such damage can be severe but is usually limited to local areas. Adult beetles are attracted tofermentingsugarandmaybefoundfeedingoninjuredfruitorvegetables.Adultsalsofeedonflowersandripeoroverlyripefruitssuchasapples,pears,peaches, and grapes.

Adultbeetlescanalsobefoundinassociationwithbacterialslimefluxes(infectionswithwhiteorcreamcoloredfoamydischargecomingoutofthetree)onwillows,poplars,andothertrees(Figs.3&4)duetothefermentationthatoccurswiththeseinfections.Becauseoftheir,andotherinsects’presence,itisfalselyassumedthattheseinsectscausedtheinfection.

BIOLOGY CONT’D

CONTROL

Fig.3.Adultbumbleflowerbeetlesfeedingonsapfromawoundedplant2.

InUtah,BFB’saresecondarypestsofminorimportance.Sincetheyprimarilyfeedonfermentingsugars,decomposingorganicmatter,andsapflowsfromplants,specificcontrolisusuallynotrequiredorrecommended.Instead,whencontrolmeasuresareneededtheyshouldbedirectedateliminatingfoodsourcesandbreedinggrounds. Adult BFB’s rarely injure crops and do not injure treeswithslimeorbacterialfluxes;itisquestionablewhetherBFB’sshouldevenbeconsideredpests.

Cultural and Physical Control Methods:Ifbumbleflowerbeetlesaredamagingcornorfruit,tryusingcultural/physicalcontrolmethodsfirst.

Sanitation: Removedecayingorganicmatterfromthevicinityoftheaffectedcrop.

Handpick: Adultbeetlecanbemanuallyremovedfromaffectedplantsandputinabucketwithsoapywater.

Chemical Control Methods:InUtah,therearenoinsecticidesthatinclude“bumbleflowerbeetle”onthelabel,butafewdoinclude“flowerbeetles,”whichlooselyincludesBFBandotherrelated beetles. These chemicals are primarily labeled foruseonturfgrassandornamentalplants,andincludetheactiveingredients:bifenthrin(3A),carbaryl(1A),chlorantraniliprole(28),halofenozide(18),imidacloprid(4A),thiamethoxam(4A),andtrichlorfon(1B).Forcontrolofbumbleflowerbeetlesoncornorfruit,insecticideslabeledforthecontrolofotherchewingbeetlepestsonthehostcropwouldprobablybeeffective.

BFBlarvaemayalsobeanuisancewhentheydisturbsoilneartherootsoftreesorplants.Giventhehabitsoftheinsect, control measures are best directed at reducing or eliminatingsuitablehabitatsbyminimizingoreliminatingorganic matter present and not attempting chemical control.Ifcontrolisneededinthissituation,systemicinsecticidessuchasimidacloprid(4A)andthiamethoxam(4A)canbeeffective.

Fig.4.Adultbumbleflowerbeetle(Euphoria sp.)feedingon corn3.

Fig.5.Larvalbumbleflowerbeetle(Euphoria sp.) and pupal cases4.

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UtahStateUniversityiscommittedtoprovidinganenvironmentfreefromharassmentandotherformsofillegaldiscriminationbasedonrace,color,religion,sex,nationalorigin,age(40andolder),disability,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.

Page3UPPDL,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.

Figs.6-9.Adultbumbleflowerbeetlelook-alikes:maskedchafer(topleft)1,tenlinedJunebeetle(topright)5, Japanesebeetle(bottomleft)6,andJunebeetle(bottomright)7.

Figs.10-13.Larvalbumbleflowerbeetlelook-alikes:Japanesebeetle(topleft)6,blackturfgrassataenus(topright)4,Junebeetle(bottomleft)8,andmaskedchafer(bottomright)1.

ADDITIONAL RESOURCESFact sheet from BugwoodWiki: http://wiki.bugwood.org/HPIPM:Bumble_Flower_Beetle More images from Bugguide.net: http://bugguide.net/node/view/2711/bgimage

FactSheetSeries:Insects–TreeFruit;SmallFruit;Vegetable;LandscapeOrnamental.

PHOTO CREDITS

Bumbleflowerbeetlelarvaeareeasilyconfusedwithlarvaeofotherrelatedscarabbeetles.OthercommonwhitegrubseasilyconfusedwithBFBarediscussedinthewhitegrubfactsheetinthelinkbelow(Figs.6-13).

May/Junebeetlegrubscommonlyfeedonturfgrassrootsandcrownsandcanberatherdifficulttocontrol.Additionaldetailspertainingtowhitegrubscanbefoundat:http://extension.usu.edu/files/publications/factsheet/white-grub07.pdf. Othercommonwhitegrubsthatmaybemistakenlyconfusedthatarediscussedinthewhitegrubpublicationincludeblackturfataeniusandmaskedchafer.

Japanesebeetle,arelatedscarabbeetlewithsimilarlookinglarvaetoBFB,isnotnativetoUtahbutisapotentiallyseriouspestthatfeedsonover200plantspecies.OneinfestationofJapanesebeetleoccurredin2006inUtahCounty.TheUtahDepartmentofAgricultureandFoodactivelymonitorsforJapanesebeetlethroughoutthestate,anditisbelievedthattheinfestationhasbeencontrolled;futuretrappingwillconfirmthesuccessoftheprogram.IfitissuspectedthatJapanesebeetlesarefound,samplesshouldbesubmittedtotheUSUPlantPestDiagnosticLaboratory.Informationconcerningsamplesubmissioncanbefoundat:http://utahpests.usu.edu/uppdl/htm/forms/.MoreinformationconcerningJapanesebeetlecanbefoundat:http://extension.usu.edu/files/publications/factsheet/ENT-100-06PR.pdf.

1.MikeRedingandBetsyAnderson,USDAAgricultural ResearchService,Bugwood.org.2.JosephBurger,Bugwood.org.3.RyanDavis,UtahStateUniversityExtension.4.WhitneyCranshaw,ColoradoStateUniversity, Bugwood.org.5.EugeneE.Nelson,Bugwood.org.6.DavidCappaert,MichiganStateUniversity,Bugwood. org.7.StevenKatovich,USDAForestService,Bugwood.org.8.ClemsonUniversity,USDACooperativeExtensionSlide Series,Bugwood.org.

LOOK-ALIKES