Invasive Species 101:A primer for Master GardenersRobert EmanuelWater Resources and Community Development Faculty,Tillamook and Clatsop counties

IntroductionWhat are invasive species?Why should we care?Biology & managementSome PNWinvadersWhat can gardeners do about them?Resources for more information.

Invasive species means an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.

http://www.sustainability.uconn.edu/sustain/biodiv/05.html

Biological invaders destroy habitats or out-compete native plants and animals.Why should we care?Invasive species costs Americans about $143 billion/year!At least 30 new potential biological invaders enter the US every day…

Understanding Biological Invasions

Definitions: Invasive Plants“Weed”ExoticsA plant growing where you do not want it.(non-native)Lots of beneficial species: Crops, pasture, forestry & ornamentals.“Noxious”A regulatory designation.“Invasive”Spreads outside of cultivation, and causes environmental& economic harm.NativesCo-evolution with other species, our natural heritage

What makes a plant invasive?Lack normal environmental constraintsFast growth and reproductionHighly adaptable a wide range of conditionsOften can transform their environmentOften encouraged by disturbanceDominance = less biodiversity

Key Stages in Plant InvasionsEscapeLag TimeInvasionIntroductionCostArea InfestedTime

What does this mean for management?People notice them hereIntroductionDetection: focus resources herePrevention or Eradication(Inexpensive)Local control and management only (Expensive)Area InfestedControl Costs Time

How do we manage invasive plants?PreventionQuarantine before introductionMonitoring & mappingChemical treatment (herbicides)Biological controls (biocontrol)Cultural treatment (hand pulling, cutting, etc.)*

Invasive Species of Horticultural Origin in Oregon

Photo - knotweed Japanese Knotweed: Fallopiapolystachyum

Glenn Miller, ODAGiant Knotweed: Polygonumsachalinese

Photo - knotweed Knotweed: Fallopiax bohemicum

Photo - English ivyEnglish Ivy: Hedera helix

Photos: Christine McDonaldPoliceman’s Helmet: Impatiens gladulifera

R. Emanuel, OSU Parrot feather: Myriophyllumaquaticum

Photo: Judy Scott, OSUYellow Flag Iris: Iris pseudacorus

Lynn Ketchum, OSU EESCCommon Gorse: Ulexeuropaeus

Photos: Michael L. ChartersSpanish Broom: Spartiumjunceum

Scotch Broom: Cytisusscoparius

French Broom: Genistamonspessulana

Photo: Paul Wray, Iowa State UniversityRussian Olive: Elaeagnusangustifolia

Photo: WikimediaPhoto: EikeWulfmeyerOld Man’s Beard, Travelers Joy: Clematis vitalba

Old Man’s Beard: Clematis vitalba

Spurge Laurel: Daphne laureola

Photo – butterfly bush infestation in Lane Co.Butterfly Bush: Buddlejadavidii

Purple Loosestrife: Lythrumsalicaria

Tree of Heaven: Ailanthus altissimaPhoto: USFS

Fennel: Foeniculumvulgare

Photo: JohnathanJ. StegemanBachelor’s button: Centaureacyanus

Desert Indigobush: Amorphafruticosa

Myrtle spurge: Euphorbia myrsintes

Leafy spurge: Euphorbia esula

Lynn Ketchum, OSU EESCEnglish Holly: Ilex aquilfolium

But wait! There’s MORE!

Salt Cedar: Tamarix spp.

Photo: University of GeorgiaHydrillaverticillata

Photo: Kurt W. HeckerothPetasites japonica var. giganteum

Photos: WA State Weed Control Board Yellow Archangel: Lamiastrumgaleobdolon

Photos: King County , WAGarden Loosestrife: Lysimarchiavulgaris

Clary Sage: Salvia sclarea

Photo: Robert Emanuel, OSUFragrant Water Lilly: Nymphaeaodorata

Only you can prevent the invasion!

What can Master Gardeners do?Know thy enemy & teach others about themGrow native & non-invasive wherever possibleHelp others to do the sameHelp the public with information on treatmentMonitor and report new invadersCheck clothes, vehicles, pets when out & about

What can Master Gardeners do?Don’t share unless you know it’s not invasiveStay away from generic wildflower mixturesWatch for hitchhikers in nursery stockUse weed-free soil and mulchWatch introductions for aggressive behaviorDon’t dump your yard clippings in the wild!

If you have a known invasive (but can’t part with it)Deadhead faithfullyUse root barriersDispose of plant material properly—bagged in the garbage or burned (completely)Please don’t share your invader with others!Contain it, control it, or cage it!

For Water GardenersAlways wash new introductions (think snails)Keep water garden separate from native watersNever dump water garden materials or water into native watersResearch your plants for invasive potential—many commonly used aquatics are!

Some Resources

http://plants.usda.gov/java/noxiousDriver

Invasive Spp. Web ResourcesPacific Northwest Weed Management Handbook: weeds.ippc.orst.edu/pnw/weedsOregon Invasive Species Hotline:oregoninvasiveshotline.org/National Invasive Species Clearinghouse: www.invasivespeciesinfo.govUSDA PLANTS Database: plants.usda.gov/index.htmlWA State Noxious Weed Board: www.nwcb.wa.gov/index.htmIdaho Weed Awareness:idahoweedawareness.net/index.htmlCalifornia Invasive Plant Council:www.cal-ipc.org Be Plantwise:www.beplantwise.org/

Questions?Robert M. EmanuelWater Resources & Community DevelopmentTillamook & Clatsop counties2204 Fourth StreetTillamook, OR 97141(503) 842-5708 X 2 robert.emanuel@oregonstate.edu