pierce county noxious weed control...

PIERCECOUNTYNoxiousWeedControlBoard

Perennial Pepperweed

Dyer’s Woad

9200 122nd St E

Puyallup, WA 98373

www.PierceCountyWeedBoard.org

Garlic Mustard

Shiny Geranium

Eggleaf Spurge

Scotch Thistle

PierceCountyNoxiousWeedControlBoardMembers

JanetAzevedo,Chairperson,District1

TerryWade,District3

ErikBalstad,District4

TomBertram,District5

JimKropf,WSUExtension

PierceCountyNoxiousWeedControlProgramStaff

BekiShoemaker,ProgramDirector

ChelliPogue&DebbieRingler,ProgramAdministrators

MorganHeileson,Education/CommunicationSpecialist

MISSIONSTATEMENT: ThePierceCountyNoxiousWeedControlBoardworks topromote responsibleweedmanagement and to reduce the harmful effects thatinvasive noxious weeds have on the people, agricultural interests, recreationalareasandnativehabitatsofPierceCounty.

2017NOXIOUSWEEDINSPECTORS

Jim Berry

Jim Bjorgen

Mary Brzezinski

Karen Carnahan

Jack Coffey

Morgan Heileson

Patti Iverson

Beverly Ivy

Melody Meyers

Jim Towslee Goatsrue

AnnualReport PierceCountyNoxiousWeedControlBoard Page2

TABLEOFCONTENTS

Introduction page 3

2017 Noxious Weed Season pages 4

Noxious Weed Infestation Breakdown pages 4‐12

Historical Comparison Chart page 12

Public Lands page 13

Noxious Weed Control Partners page 14

Public Outreach and Education page 15

Pie Chart of Noxious Weed Sites page 16

Flowering Rush Project page 17

Class ‘A’ Updates page 17‐18

Bike Trail Pilot Program page 18

Variable‐Leaf Milfoil Project page 19

IWC Project, Jennifer Andreas page 20‐21

Maps page 22‐32


INTRODUCTION

In 1975, concerned landowners petitioned county government to initiate a program to stop theaggressive spread of Tansy Ragwort. The Pierce County Noxious Weed Control Program wasestablishedin1977inresponsetotheirconcernsinaccordancewithRCW17.10.Thecouncildividedthecountyintofiveweeddistrictsandappointedaboardmemberfromeachdistricttoserveuptotwofour‐yeartermsontheBoard. AllboardmembersareappointedbytheCountyExecutiveandconfirmedbytheCountyCouncil.

The NoxiousWeed Control Program is responsible for administeringWashington State’s NoxiousWeedControlLaw(RCW17.10).Thenoxiousweedprogramservesasaneducationandenforcementagency,assistinglandownersintheidentification,controlandpreventionoftheinvasiveplantspecieslistedinChapter16‐750oftheWAC.

Theweed control programprovides the citizens of Pierce Countywith information about noxiousweeds and their harmful effects. The Weed Board staff offers technical recommendations,informational literature, educational workshops, and community outreach events concerning thedamaging impact that these non‐native invasive species have on our community. NoxiousWeedinfestationscostfarmersmillionsofdollarsannuallyinlostagriculturalproductivity.NoxiousWeedscan compromise public health and safety, lower property values, degrade recreational and timberlands, increase floodhazards,reducebiodiversity,andthreatennativeecosystemsandendangeredspecies.

Noxious Weed Inspectors survey both publicand private properties, alerting landownersandcommunitymunicipalitiestothepresenceof noxious weeds on their property andcoordinatingwiththemtoachieveweedcontrolin compliance with the state weed law RCW17.10. Inspectors work with landowners todevelopeffectiveweedcontrolstrategieswhichsupport the program’s control efforts andcomplywiththestatelaw.


THE2017NOXIOUSWEEDSEASONTheseasonstartedoutwiththePierceCountyNoxiousWeedControlBoardfindinganewhomeattheSewerandTrafficOperationsFacilityonSouthHillinPuyallup;alsoknownastheSTOPfacility.

Duringthewinterof2017thePugetSoundareahadanotheryearofrecordprecipitation,followedbyoneofthewettestspringsonrecord.Infact,the122‐year‐oldrecordforwettestperiod(October‐April)wasbrokenearlierthisyear,drenchingtheregionwith44.69inchesofrain.Havingsucharainyspringpointedallindicatorstoidealconditionsforthosenoxiousweedsthatthriveinsaturatedhabitats.ThewetseasoncontinuedthroughmostofMaybeforetheweatherdidacompleteturnaboutandgaveusoneofthedriestandhottestsummersseeninthePacificNorthwestsincerecord‐keepingbeganattheSea‐TacAirportin1945.BetweenJune21standSeptember21strecordsatSea‐Tacshowedonly0.52inchesofrainfall,0.06incheslessthanthepreviousrecord.ItwasalsonotedthatthePNWtiedtheaverage high temperature for that time period at 78.6 degrees; about 4 degreeswarmer than theaverage. Moving from an extremely wet spring, straight into a dry summer, pointed towards thenoxiousweedsflourishingearlyandprogressingthroughtheirlifecyclecomparativelyquick.Thisyearhasseenaverydifferentoutcomethanlastseason.Thosespeciesthatprosperinmoistconditionshavethrived,whereasweedsthatsucceedindryhotclimatesdidnotreachthenumbersobservedlastyear.AnewrecordhighofPoisonHemlock infestationsoccurred thisseasonat471 infestations;a61%increasefromthepreviousseason.Itwasfoundatsitesfromlastyear,aswellasdiscoveredinnewsitesthroughoutPierceCounty.Mostnoxiousweedssawadramaticincreaseordecreaseinnumbers,withveryfewspeciesremainingthesameasthepreviousseason.

Throughout the 2017 weed season, noxious weed inspectors surveyed and identified 3,058 sitescontainingnoxiousweedsandmonitored460inactivesites.Sincesomesitescontainedmorethanonespeciesofnoxiousweed,theseasontotaled3,271noxiousweedinfestations.NWCBstaffservedthecommunitybyprovidingadvice,instruction,technicalrecommendations,andenforcementofnoxiousweedcontrollaws.Theyconducted367phoneconsultationsandmeton‐sitewith362landownerstodevelopasitespecificintegratedweedmanagementstrategy.

NOXIOUSWEEDINFESTATIONS

TANSYRAGWORTSenecio jacobaea – Class B2422Sites13%decrease



POISONHEMLOCKConium maculatum‐ClassB 471Sites61%increase

SPOTTEDKNAPWEEDCentaurea maculosa – Class B182Sites26%decrease63inactivesitesmonitored

WILDCHERVILAnthriscus sylvestris – Class B79Sites61%increase



COMMONFENNELFoeniculum vulgare – Class B46Sites70%increase

GIANTHOGWEEDHeracleum mantegazzianum – Class A18Sites260%increase

SHINYGERANIUMGeranium lucidum – Class B17Sites41%increase



MEADOWKNAPWEEDCentaurea x moncktonii – Class B17Sites6%increase

GORSEUlex europaeus – Class B10Sites68%decrease21inactivesitesmonitored

DALMATIANTOADFLAXLinaria dalmatica – Class B2Sites78%decrease7inactivesitesmonitored



PERENNIALPEPPERWEEDLepidium latifolium – Class B2sites1inactivesitemonitored

GOATSRUEGalega officinalis – Class A

1Site

DYER’SWOADIsatis tinctoria – Class A1Site



ORANGEHAWKWEEDHieracium aurantiacum – Class B1site2inactivesitesmonitored

YELLOWHAWKWEED Hieracium caespitosum – Class B1Site

DIFFUSEKNAPWEEDCentaurea diffusa – Class B2inactivesitesmonitored



FLOWERINGRUSHButomus umbellatus – Class A3inactivesitemonitored

MILKTHISTLE Silybum marianum – Class A

4inactivesitesmonitored

BLUEWEEDEchium vulgare–ClassB4inactivesitesmonitored



RUSSIANKNAPWEEDAcroptilonrepens–ClassB1inactivesitemonitored

EGGLEAFSPURGEEuphorbiaoblongata–ClassA1inactivesitemonitored

GARLICMUSTARDAlliaria petiolata – Class A2inactivesitesmonitored


RUSHSKELETONWEEDChondrilla juncea – class B1inactivesitemonitored

HISTORICALCOMPARISONCHART

YEAR

NOTICES

WORKORDERS

VIOLATIONS

TOTALINFESTATIONS

2017 2017 1041 14 3,271

2016 2001 1171 8 3,462

2015 1824 1098 31 3,257

2014 2329 1404 33 3,733

2013 2579 1358 41 4,114

2012 2226 1162 35 3,655

2011 2016 728 87 2,333

*Pleasenote:SomeNotices&WorkOrderscontainmorethanonenoxiousweedand/ormayreferencemorethanoneparcel

Miles of Rights‐Of‐Way Surveyed: 29,417

Total Number of Notices & Work Orders Issued: 3,058

Non‐Complied Violations Resulting in Contractor Clean‐up & Fines Imposed: 1


PUBLICLANDSANDROADWAYS

The Noxious Weed Control Program isresponsible for overseeing the weedcontrolcomplianceeffortsofthe21citiesand45othergovernmentalagencieswhoown,ormanagelandswithintheCounty.PierceCountycoversatotal landareaof1,806 square miles, or approximately1,155,840acres.Thereare1,613milesofroadway in unincorporated PierceCounty. During the growing season of2017, Field Inspectors surveyed county,

municipal, and state roadways, andotherpubliclyowned lands, inorder to identifynoxiousweedinfestations.Atotalof1,041noxiousweedinfestationworkorderswereissuedin2017forroadsiderights‐of‐way.Manyofthesesitescontainedmorethanonespeciesofnoxiousweedandextendedoverlongstretchesofroadway.Largeinfestationswerecontrolledbytheresponsibleagenciesand771smallinfestationswereclearedbyNoxiousWeedFieldInspectors.Ofthesitesfoundonpubliclands,440werelocatedalongroadwaysinunincorporatedPierceCounty.Inspectors also identified 100 infestation sitesalongroadswithinthevariouscitiesandtownsofPierce County, or along Washington StateDepartmentofTransportationrights‐of‐way.Oncean infestationsite is locatedand identified,weedboardstaff createuniquelydesignedWorkOrders and corresponding GIS maps, to complywiththediverserequirementsofeach individualagency.WorkOrdersaree‐maileddirectlytothemanagers and crews of each department withintheappropriateagenciesresponsibleforNoxiousWeedcontrolcompliance.Inspectorsmonitorallsitestoensurethatallinfestationsarecontrolledinaccordancewithstatelaw.

Spotted Knapweed City of Tacoma Roadside

Orange Hawkweed Pierce County Roadside


MUNICIPALITIES SCHOOL DISTRICTS

City of Auburn City of Bonney Lake City of Buckley City of Dupont City of Eatonville City of Edgewood City of Fife City of Fircrest City of Gig Harbor City of Lakewood City of Milton City of Orting City of Pacific City of Puyallup City of Roy Town of Ruston City of Steilacoom City of Sumner City of Tacoma City of University Place City of Yelm

Bellarmine Prep Bethel School District Clover Park School District Clover Park Technical College Fife School District Franklin Pierce School District Pacific Lutheran University Peninsula School District Pierce College – Puyallup Campus Pierce College – Steilacoom Campus Puyallup School District Steilacoom Historical School District Tacoma Community College Tacoma School District University Place School District White River School District

OTHER AGENCIES Burlington Northern Santa Fe Railroad Cascade Water Alliance Chambers Bay Golf Course Fort Steilacoom Golf Course Joint Base Lewis McChord McNeil Island Metro Park District Tacoma Penn Met Park District Port of Tacoma Puget Sound Energy Puyallup Tribe of Indians Sound Transit Tacoma Firs Golf Course Tacoma Housing Authority Tacoma Rail Union Pacific Railroad Washington State Department of Transportation Washington State Fish & Wildlife

PIERCE COUNTY AGENCIES & DEPT. Environmental Services Facilities Management

Ferry and Airport

Fire Prevention

Pierce County Parks & Recreation Pierce Conservation District

Pierce County Sewer Pierce County Sheriff Pierce Transit Public Works

Surface Water Management

PRIVATE LANDOWNERS & MANAGERS


PUBLICOUTREACHANDEDUCATIONTheNoxiousWeed Control Board activelypursues opportunities to increase publicawarenessregardingtheharmfuleffectsofnoxiousweedsandtheiridentificationandcontrol. To that end, a wide variety ofhelpful, informative literature is madeavailable to the public free of charge.Throughout the year the Noxious WeedEducation Booth and staff are on hand atvarious community fairs and eventsproviding information on noxious weeds.Also, the program’s Biologist & EducationSpecialist presents noxious weed trainingworkshops to vegetation managementcrewsandvariouscommunitygroups.Alloftheseoutreachopportunitiesareessentialtotheprogram’soverallweedcontroleffortsandserveto encourage a spirit of stewardship and teamwork between Noxious Weed Board staff and thecommunitytheyserve.

EDUCATIONPRESENTATIONS&OUTREACHSTATISTICS

TacomaHome&GardenShow 817

SpringFairBooth 517

WashingtonStateFair 2836

On‐SiteLandownerConsultations362

PhoneConsultations 367

KeyPeninsulaAdvisoryCommittee7

TahomaFuchsiaSociety 18

MasterGardener’sAssociation 120

KeyPeninsulaCityCouncilCommittee29

SurfaceWaterManagementInspectors15

WebsiteVisitors 41,242

TOTALEDUCATION&OUTREACHCONTACTS46,330

Education Booth


2017NOXIOUSWEEDINFESTATIONS

Tansy Ragwort, 242213% decrease

Poison Hemlock, 471

Spotted Knapweed, 18226% decrease

Wild Chervil, 79

Common Fennel, 46

Giant Hogweed, 19

Shiny Geranium, 17

Meadow Knapweed, 17

Gorse, 1068% decrease

Dalmation Toadflax, 278% decrease

Perennial Pepperweed, 2

Dyer's Woad, 1

Orange Hawkweed, 1

Yellow Hawkweed, 1

Goatsrue, 1


FLOWERINGRUSHPROJECT

The first recorded infestation of Flowering Rush(Butomusumbellatus)wasidentifiedinPierceCountyin2014.FloweringRushisaClassA,aquaticnoxiousweedfoundalonglakeshoresandslow‐movingrivers.It aggressively colonizes and can spread by seed,bulbilsandrhizomefragments.

Surveys in 2015 revealed the presence of FloweringRush in Chambers Lake and Shavers Marsh on thesouthernboundaryofJointBaseLewisMcChordandseveralsmallinfestationsdownstreamonMuckCreek inthetownofRoy.SurveysfurtherdownstreamalongMuckCreekandalongtheNisquallyrevealednofurtherinfestationsofButomus. 2016 showed an encouraging decrease inButomus populations. The JBLM crew treated 2.36 acres ofFloweringRushatShaverLakeandonly .02acresatChambersLake.DownstreamfromJBLMonlytwosmallinfestationswerefoundalongMuckCreek,onprivatelyownedland.AttheendofSeptember2016,are‐inspectionofthearearevealednonewplants.

In2017ChambersLakeandShaversMarshwereonceagainsurveyedforFloweringRush.NopresenceofB.umbellatuswasfounddownstreamonprivatelyownedland,howeverJBLMisstillfightingtheongoinginfestationsontheirproperty.

CLASS‘A’UPDATES

Class‘A’noxiousweedsarehighpriorityinPierceCounty.EradicatingtheseweedsareofupmostimportancebeforetheybecomethenextScotchBroomorHimalayanBlackberries.Earlydetectionandrapidresponse(EDRR)iskeywhendealingwithnoxiousweedsclassifiedinthiscategory.

PierceCounty’sfirstrecordedinfestationofGoatsrue(Galegaofficinalis)wasidentifiedthissummer.GoatsrueisaClass‘A’,herbaceous perennial found in irrigation waterways,cropland, ditch banks andwetland communities. It createsaggressivemonoculturesandspreadsbyseed.

SurveysthissummerdiscoveredtheexistenceofGoatsrueatthe tide flats in Tacoma. Prompt action was taken bylandowners and contractors to control the infestation. No

otherreportsofGoatsruehavebeenfoundasofmid‐October.

Dyer’sWoad,awinterannual,biennialorshort‐livedperennial, canbe found inpastures, forest lands and rangelands. This Class ‘A’ noxious weed has been in

Goatsrue

Goatsrue

Dyer’s Woad

Flowering Rush


PierceCountyforseveralyears.Itreproducesbyseedonly.Fortunately,thisplanthasseenadeclineinthenumberofplantssinceitsdiscoveryinthearea.Asofthisyear,onlythreeplantswerefoundattheexistingsiteandwerepulledbyoneofourfieldinspectors.

In2015EggleafSpurgewasfirstintroducedinPierceCounty.Thisuprightperennial Class ‘A’ noxious weed can be found in streambanks, dampmeadows,andwasteareasandonroadsides.EggleafSpurgereproducesbybothseedandbudsfromtherootcrown.Landownerswerenotifiedofthe infestationandquicklycontrolled the infectedsite.For thepast twoyearstherehasbeennoknownpresenceofthisClassAnoxiousweed.

BikeTrailPilotProgram&HorsebackRidingThisseasonbegananewpilotprogramforthePierceCountyNoxiousWeedControlBoard.Duringthe2016seasontherewasanincreaseinphonecallstoourdepartmentaboutnoxiousweedslocatedonbiketrailsinPierceCounty.Theprogramdirectorandstaffrealizedthesepathswerenot monitored enough, therefore an initiative was taken to improve themonitoringofthoseroutesduringthe2017season.Withtheapprovaloftheboard,andthemutualagreementwiththe field inspector, thebiketrailpilotprogramwasshaped.

Theprogramwascreatedtoseparatebiketrailsintoone field that an inspector exclusively focused on.Throughout the 2017 season, one field inspectorcycledalongseveraltrails including,butnot limitedto,FoothillsTrail,CushmanTrail,SumnerLinkTrailandthePuyallupRiverWalkTrail.Theprogramhelpedspreadmoreawarenesstothepublicandtosomepartneragenciesaboutnoxiousweedsandprovidedlocationsofinvasiveplantsalongthetrails.

Asofmid‐October,theprogramhasbeenagreatsuccess.Over169milesofbikepath have been travelled this season and the number of noxious weed infestations that have beencontrolledhasincreased.AddingthisprogramhasgivenotherfieldinspectorstheopportunitytospendmoretimeontheroadtocontrolregulatedinvasiveplantsthroughoutPierceCounty.

PierceCountyhasmanydiverselandscapes,someofwhicharetoodifficulttowalkthroughandarenotaccessibleonbike.Forthoseregions, especially in the Timberland areas, one of our fieldinspectors uses horseback riding as a great tool to get to thoseimprobable places in search for noxious weeds. This not onlyincreasestheareathatinspectorsmonitorinthecounty,butalsoillustratesthediversity,passionandindividualityamongourstaff.

Eggleaf Spurge

Bike Trail Inspector

Horseback Inspector


VARIABLELEAFMILFOILPROJECTThePierceCountyNoxiousWeedControlBoard,incooperationwiththeWashingtonStateDepartmentofEcology completed its ninth year of a Variable‐Leaf Milfoil control project. Variable‐Leaf Milfoil,Myriophyllumheterophyllum, is a Class ‘A’ aquatic noxiousweed,meaning that eradication is requiredthroughoutthestate.Itisasubmergedspeciesthatwillgrowinwaterdepthsofupto20feet.Onceitreaches the surface of the water the plant forms dense surface mats that potentially create seriousnavigationandsafetyhazardsfromentanglementissues.CurrentlyLakeJosephineandLakeFlorencecontaintheonlyknownvariable‐leafmilfoil infestationsinPierceCounty.ThesetwoAndersonIslandlakesareconnectedbyasmallchannel,sothatwaterflowsfromLakeFlorenceintoLakeJosephineduringperiodsofhighwater.Avarietyofmethodshavebeenusedoverthelasttenyearstotreattheseinfestations,includingchemicaltreatmentswherenecessary,andmanualhandremoval,usingscubaandsnorkel.

FLORENCELAKE–2017

o April12–Poorvisibilitydue to rainonwater surface.FoundVariable‐LeafmilfoilonSEshore,handpulledplantsin2locations,found2plantsonNEshoreinanewarea,pulledonbuttheotherwastoodeep.

o June8–QuiteafewmilfoilplantsseenonSEshoreandafewonNEshore.Handpulledtheshallowonesonly.Also,foundoneplantWestofthelaunch,onSshore,handpulledit.

o June28–Eastendoflaketreatedwith2,4‐DestertocontroltheVariable‐LeafMilfoil.o Sept.19–HandpulledafewplantsfromshallowsofSEshoreamongdownedtrees,about1

poundtotal.Surveyedwholeshoreline,anddidnotseeanyadditionalplants.

JOSEPHINELAKE–2017

o April12–SomelargeVariable‐LeafmilfoiljustEastoflaunchandalsoSouthofdockonNWshore,bothinandnearcattails.Suggeststhattheyover‐wintered.AfewontheSouthshore,pulledabout10‐15lbs.wetweight

o May9–MoreplatsfoundinthesameareasasApril,handpulled32poundsofwetweighto June8–FoundmuchlessVariable‐LeafMilfoil,about2poundswetweightpulledo July31–MoreVariable‐LeafMilfoilagaininthesameareasatNorthendoflake,noneseen

attheSouthend.Pulled61lbs.wetweighto Sept.19–OnlymanagedtodopartoftheNorthend.ManyVariable‐LeafMilfoilplantsfound,

pulled7partialbags,estimated150lbs.wetweightCLEARLAKE–2017

o 2017 – Surface survey fromboat in earlyOctober, nomilfoil of either kind (Eurasian orVariable‐Leaf)observed


2016INTEGRATEDWEEDCONTROLPROJECTBIOCONTROLRELEASEREPORTJenniferAndreasIntegratedWeedControlProjectDirectorWSUExtension–PuyallupResearchCenter“WashingtonStateisfacinganinvasionofnon‐native,highlyinvasivenoxiousweeds,includingknapweeds,purpleloosestrife,St.Johnswort,CanadaThistle,YellowStarthistle,andDalmatianToadflax.Non‐nativenoxiousweedsdestroybiologicaldiversity,fueldevastatingwildfires,decreaseforage,increaseerosionpotential,anddecreaselandvaluesacrossthestateandwesternUSA.WashingtonStatelandownersandlandmanagersoftendonothavethetime,fundsorexpertisetoimplementanintegratedcontrolstrategy.TheIntegratedWeedControlProject(IWCP)assistswithimplementationbyprovidingbiologicalcontrolagentsfreeofchargetothosewithappropriatereleasesites.Inaddition,ourprojectfurtheraddressesthisneedbyeducatingandengaginglandmanagersandlandownersforabetterunderstandingofinvasiveweedissuesandtheimportanceofprevention,earlydetection/rapidresponse,integratedmanagementtoolsandrestorationtosolvetheirownweedproblems.”

PRESENTATIONBiocontrolofNoxiousWeeds.Presentedatthe2017PesticideRecertificationWorkshop.WSUUrbanIPMandPesticideSafetyEducation.Puyallup,WAJANUARY‐DECEMBER2016RELEASEINFORMATION:

9releases 3,550biocontrolagents(BCA) 7biocontrolagentspeciesusedtocontrol5weedspecies

Spottedknapweed Larinusobtusus(seed‐feedingweevil):1release,250insectstotal

Purpleloosestrife Galerucellaspp.(foliage‐feedingbeetle):1release,200insectstotal Hylobiustransversovittatus(root‐miningweevil):1release,100insectstotal

Scotchbroom Bruchidiusvillosus(seed‐feedingbeetle):3releases,852insectstotal Exapionfuscirostre(seed‐feedingweevil):1release,48insectstotal

CanadaThistle Urophoracardui(gall‐formingfly):1release,100insectstotal

Hedgebindweed Aceriamalherbae(gallmite):1release,2000mitestotal

PASTRELEASEINFORMATION:

2016:13releasesof4,550BCA(7BCAspecies;4weedspecies) 2015:15releasesof3,957BCA(7BCAspecies;5weedspecies) 2014:11releasesof3,588BCA(4BCAspecies;3weedspecies)


2013:15releasesof4,575BCA(5BCAspecies;4weedspecies) 2012:4releasesof885BCA(4BCAspecies;2weedspecies) 2011:13releasesof4,170BCA(6BCAspecies;5weedspecies) 2010:25releasesof36,971BCA(9BCAspecies;8weedspecies) 2009:14releasesof4,090BCA(6BCAspecies;6weedspecies) 2008:15releasesof3,708BCA(5BCAspecies;4weedspecies) 2007:15releasesof3,526BCA(7BCAspecies;6weedspecies) 2006:17releasesof4,368BCA(12BCAspecies;6weedspecies) 2005:13releasesof4,337BCA(6BCAspecies;5weedspecies)

ADDITIONAL WORK:

MonitoredScotchBroomseedpodattackbyBruchidiusvillosus(BRVI)andExapionfuscirostre(EXFU)fromPierceCountysitesinLakewood.TenadditionalsitesweresampledfromwesternWA.

Podsarestillbeingdissectedanddatastillneedstobeanalyzedfor2017. Lakewood–SouthSoundWildlifeAreasite:

2017–dataanalysisunderway 2016–83.0%seedreduction(76.1%BRVI,23.3%EXFU);4%parasitism 2015–85.4%seedreduction(71.1%BRVI,28.9%EXFU);22.8%parasitism 2014–30.6%seedreduction(70.6%BRVI,29.4%EXFU);8.8%parasitism 2012–47.3%seedreduction(18.2%BRVI,81.8%EXFU);38.3%parasitism

SurveyedBayLakebykayaktoassesspurpleloosestrifeandGalerucellaspp.populations.Althoughpurpleloosestrifeisfoundonshoreedgesaroundtheentirelake,thedensestpatchesareinNEpartofthelake,whichdrainsintothePugetSound.Galerucellaspp.wasfoundatdamagingandcontrollinglevelsaroundthelakeexceptinareaswiththedensestloosestrife(NEcorner).SinceGalerucellaspp.tendstopreferdensepopulationsofloosestrifetosmallpatches,itislikelythatotherfactorsareinfluencingtheweed/biocontrolsystem.Threepotentialfactorscouldbeinvolved:1)waterlevelsaretoohighwhichdonotallowtheinsecttocompleteitslifecycle,2)thisareaofthelakemightbeslightlytidally‐influencedresultinginregularwaterfluctuationswhich,again,aredisruptingtheinsect’slifecycle,or3)insecticideusedtocontrolbackyardpestsormosquitoesmaybeaccumulatingatthedrainagepointofthelakeandimpactingGalerucellaspp.survival.Theroot‐miningweevil,Hylobiustransversovittatus,appearstobemoretolerantofhighwaterandregularlyfluctuatingwatersothisinsectwasreleasedattheNEcornerofthelake.IttakesmanyyearstoconfirmestablishmentandseeimpactsofH.transversovittatusandadditionalreleasesarerecommended.Wewillcontinuetoassessthissiteinfutureyears.

pierce county noxious weed control...

Documents