Asian Mustard(Brassica tournefortii)

•18-36in.tall;basalrosetteupto36in.wide•PlantssetseedpriortoApril•Seedpodsupto21/2in.long•Basalrosetteleaveshairy;pinnatelylobed&withtoothedmargins•Seedslightreddishbrownorblack

Flowering rush(Butomus umbellatus)

•Upto5ft.tall•Aquaticperennial•Bloomslatesummer•Flowers1in.wide•Leavesbasal,sword-like&upto3ft.tallby1/2in.wide•Thick,creapingrhizomes•Stemstriangular•Fruitsbrown,1/2in.long•Toleranttoawidetemperaturerange

Common reed (Phragmites australis)

•6-15ft.tallperennialgrass•Spreadsbyrhizomes•Formsdensethicketsinornearwater•BloomsJulytoOctober•Flowersfeathery&drooping;canappearsilveryorpurplish•Leavesblue-green,flat,smooth•NativespeciesofPhragmitesalsoexistinColorado

Cogongrass(Imperata cylindrica)

•Upto6ft.tall•Colony-forming•Flowers2-8in.;fuzzy•Leaves1/2to3/4in.widewithoff-centerwhitishmidrib,finelyserratedmargins&asharp,pointedapex•Rhizomeswhitish,scaly&sharp

Himalayan blackberry(Rubus armeniacus)

•Upto15ft.tall•Thicket-formingshrub•Bloomslatespringtosummer•Flowers1in.ingroupsof3-20•Compoundleavesdarkgreenabove&paletowhitishbelow;leaveson1styearshootshave5leaflets&leaveson2ndyearsideshootshave3leaflets

Common bugloss(Anchusa officinalis)

•1-2ft.tallby1-2ft.wide•BloomsJunetoOctober•Flowers1/2in.brightbluetopurplewithwhitethroats•Stems&leavesfleshy&hairy•Leavesnarrow&slightlypointed;alternate&getsmallerupstem•Fruit4-chamberednutlet,1seedeach

Meadow hawkweed(Hieracium caespitosum)

•1-3ft.tall•BloomslateMaytoJune;flowerheadsintightclusters;5-30headsperstem•Leavesmostlybasal;lanceshaped,upto6in.long&hairy;formdensematatbase•Stems,leaves&bractshavedenseblackishhairs&exudemilkysapwhenbroken

Onionweed(Asphodelus fistulosus)

•11/2-21/2ft.talltuftedclumps•BloomsJulythroughAugust•Flowers1/4to1/2in.wide•Stemsbranched&hollow•Leaves3-14in.longby1/4in.wide•Doesn’tsmelllikeonion&doesn’tformbulb•Seedstriangularincross-section;sharpedges

Baby’s breath (Gypsophila paniculata)

•12-18in.tall&upto16in.wide•Bloomssummerthroughfall•Flowersclustered,delicate,whiteorpink,5-parted•Leaveslinear-lance-shaped,hairy,opposite;3/4to4in.long•Seedcapsulesegg-shaped,lessthan1/10in.,verysmall&blackish

Garlic mustard(Alliaria petiolata)

•1-4ft.tall•Herbaceousbiennial•Bloomsearlyspring•Flowerssmall;4whitepetals•Rosetteleaves1-6in.&heart-shaped•Matureseedsshinyblackinerect,slendergreenpodsthatturnpalebrown•Garlicodorwhenplantpartscrushed•Highlyshade-tolerantR

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Hairy willow-herb(Epilobium hirsutum)

•3-6ft.tall;perennial•BloomsJunetoAugust•Flowerssingle,1/2to1in.•Stemscoveredinsofthairs•Seedswithwhitesilkytuftinlongseedpod•Leaves1/2in.wide,2-4in.long,opposite,lance-shapedwithtoothededges;attacheddirectlytostem•NumerousnativespeciesarefoundinCOwetlands

Brazillian Elodea(Egeria densa)

•Upto6ft.long;densesubmergedaquaticperennial•Canliverootedorfreefloating;upto20’deep•Flowersemergentonstalkswith3whitepetals&3greensepals•Brightgreenleavesinwhorlsof4;linear,oblong,1¼”w/veryfinelytoothedmargins•Fragmentedpiecescanproducenewplants

Purple pampasgrass(Cortaderia jubata)

•1-2ft.tallby1-2ft.wide•BloomsJunetoOctober•Flowers1/2in.brightbluetopurplewithwhitethroats•Stems&leavesfleshy&hairy•Leavesnarrow&slightlypointed;alternate&getsmallerupstem•Fruitsare4-chamberednutletswith1seedeach

Scotch broom(Cytisus scoparius)

•7ft.tallby31/2ft.wide•Bloomslatespringtoearlysummer•Flowers1in.&pea-like•Trifoliateleavesdarkgreenabove;paler&fuzzybelow;alternate&pinatelycompound;1/2-1in.wide•Groovedstemsupto2in.wide•Flatseedpodswithsmallblackseeds

Sericea lespedeza(Lespedeza cuneata)

•3to6ft.tall•Bloomssummertofall•Flowersinclustersof2-4•Leavesthin,alternate,abundant&three-parted;leaflets1/2-1in.withwedge-shapedbases;hairy•Onetomanyslenderstems

Spiny cocklebur(Xanthium spinosum)

•1-4ft.tallby1-4ft.wide•BloomsJunetoJuly•Flowers1-11/2in.;creamygreen•Stemstraight&ridgid•Leavesalternate,upto3in.long&11/2in.wide;3-lobed;shiny•Femaleflowersbecomeburrswhicharethefruits;egg-shaped

Woolly distaff thistle(Carthamus lanatus)

•31/2ft.tall•BloomsJulytoAugust•Flowers1-2in.widewithspinybracts•Palegreenstemshairy,rigid,upperportionbranched•Plantspersistuprightaftertheyhavedied•Flowerssimilartoyellowstarthistle

Yellow flag iris(Iris pseudacorus)

•3-4ft.tallwetlandperennial•Bloomslatespringtoearlysummer•Flowersbrightyellowwith3droopingsepals&3smaller,uprightpetals,3in.wide&ingroupsof2-10•Leavesarisefrombase,flatwithraisedmid-rib;rhisomesgrowupto20ft.•Fruitsoccuras2in.browncapsules

Yellowtuft(Alyssum murale & A. corsicum)

•Perennialforbs•Adaptedtoserpentinesoils•Flowersareyellow,small&plentiful,occurringonbranchedumbels•Bloomearlysummer•Fruitsarepapery,circulartoovalandflattened

• A.muralehasnarrow,gray-greenleaves&A.corsicumhasovalsilvery-grayleaves

Water lettuce(Pistia stratiotes)

•2-3ft.tall;densefloatingaquatic•Bloomslatesummertowinter•Flowersinconspicuous;clusteredonsmall,fleshystalkinleafaxils•Leavesvelvety,hairy,spongy&inrosettes;6in.long;connectedbyshortstolons•Rootsnumerous&feathery

White bryony(Bryonia alba)

•12ft.longormore;vigorousvine;cangrow6in.perday•Bloomsmid-summer•Flower1/2in.wide&greenish-white•Leavesaredarkgreenandpalmatelylobed;eachhasacorkscrewtendrilforclimbing•Highlytoxicseedsinround,blackfruit•Formsdensemats&shadesoutvegetation

Parrotfeather(Myriophyllum aquaticum)

•Denseaquaticperennialwithbothsubmerged&emergentleaves•Emergedleavesbrightblue-green;submergeddarker;4-6whorledateachnode•Emergedstemsgrowupto1ft.abovewater•Flowersmayoccur;ifso,white&1/16in.long•Spreadsbyplantfragments

Water hyacinth(Eichhornia crassipes)

•Upto3ft.tall;densefloatingaquatic•Formsdensethicketsinwater•BloomsJulytoOctober•Flowers2in.wideinclustersattheendofa12-in.spike•Leavesdarkgreen,11/2to41/2in.wide&6in.long•Featheryroots

Yellow floatingheart(Nymphoides peltata)

•Floatingaquaticperennial•Carpetswatersurfacewithlong-stalked,heart-shaped,opposite&unequalleaves;2-6”long&wide;arisingfromrhizomes•Flowersbrightyellow;2-5perstalk;1”indiameter;5petalswithfringededges•FlowersJunetoSeptember•Seedsflat&ovalinshape;containedinbeakedcapsule

Swainsonpea(Sphaerophysa salsula)

•Upto5ft.tall•BloomsMaytoJune•Flowers1/4-1in.long,pea-shaped,&ingroupsof4-8•Leavescompoundpinnate,alternate;9-25ovalleafletswithsilveryhairs•Seedsformininflatedbladder-likepods•Woodytaprootwithspreadingrhizomes

Syrian beancaper(Zygophyllum fabago)

•Upto3ft.tallby3ft.wide•BloomsMaytoAugust•Flowerscanbewhite,yelloworsalmoncolor&have10-12orangestamens•Stemssucculent&multi-branched•Leavesopposite,compound&with2thick,fleshyleaflets

*PhotoscourtesyOregonDept.ofAgriculture