Invasive Weeds Of Eastern Washington
Invasive Weedsof Eastern WashingtonWSU Extension Manual EM005
Invasive Weedsof Eastern WashingtonStephen M. Van Vleet, Ph.D.Washington State UniversityWhitman County ExtensionIntroduction3. Contain established weed populations bytreating perimeter plants.4. Restore and maintain healthy nativeplant communities.The rapid spread of invasive plants threatensnatural resources across the United States, andthe Pacific Northwest is no exception. Invasivespecies displace natural plant communities andhave the following impacts: Degraded and destroyed wildlife habitat Reduced plant and animal diversity Impaired land productivity Obstructed waterways and reduced waterlevels Erosion Fire hazards Restricted recreational activities Reduced land values Need for costly restorationThe control of any weed begins with earlydetection. The objective of this guide is to aidin the identification and control of invasiveweeds found in eastern Washington. For furtherinformation about noxious weed identification,control options, and control requirements understate law, please contact your local noxious weedcoordinator (listed by county at http://www.nwcb.wa.gov/Contact%20Us/county coordinators.htm) or aWashington State University Extension educator.Always wear protective clothing, includinggloves, when pulling weeds. Many weed speciescontain toxins that may cause mild to severedermatitis. If using herbicides, it is important totake additional precautions.Prevention is by far the most effective approachin dealing with invasive plants. For best results,incorporate as many preventive practices asfeasible into your land management strategy:1. Monitor property for invasive plantspecies.2. Avoid introduction of invasive species:a. Do not plant known invasive speciesor use wildflower mixes in gardens orlandscaping.b. Avoid driving through infested areas.c. Clean equipment, vehicles, andmaterials before leaving infestedsites.d. Use only weed-free seed, soil, and feed.e. Limit soil disturbances and revegetatedisturbed ground with desirablespecies.f. Contain animals that have fed onweed-infested forage for at least 3days to allow pass-through of weedseeds.g. Dispose of aquarium plants awayfrom natural waterways.h. Monitor beneath bird feeders forinvasive plants.Use Herbicides With Caution! Before using any chemical, always readthe label carefully and closely follow theinstructions. Warnings include wearingprotective clothing and safety deviceswhen storing, handling, and applyingherbicides.Some chemicals may not be registered inyour area or may have restricted use, sobeware of usage restrictions.Be aware of your legal responsibilities asa pesticide applicator. You may be liablefor injury or damage resulting fromherbicide use.This handbook is not intended as acomplete guide to herbicide use.Washington State University and its employeesare in no way responsible for the misuse of anyproducts or damages caused by any productsmentioned in this publication to control thespecified weeds.1
Index of Invasive Plants by Common NameCommon NameScientific NamePagesBlack henbaneHyoscyamus niger L.5Canada thistleCirsium arvense (L.) Scop.6Common buglossAnchusa officinalis L.7Common groundselSenecio vulgaris L.8Common tansyTanecetum vulgare L.Dalmatian toadflaxLinaria dalmatica (L.) Mill.910, 11Diffuse knapweedCentaurea diffusa Lam.Hoary cressCardaria draba (L.) Desv.; Lepidium draba L.12HoundstongueCynoglossum officinale L.Japanese knotweed; giant knotweed;Bohemian knotweedPolygonum cuspidatum Siebold & Zucc.; Fallopia sachalinensis(F. Schmidt ex Maxim.) Ronse Decr.; Polygonum x bohemicum(J. Chrtek & Chrtkovß) Zika & JacobsonKochiaKochia scoparia (L.) Schrad18Leafy spurgeEuphorbia esula L.19Meadow hawkweedHieracium caespitosum Dumort20Musk thistleCarduus nutans L.21Orange hawkweedHieracium aurantiacum L.22Oxeye daisyLeucanthemum vulgare Lam.23Perennial pepperweedLepidium latifolium L.24Plumeless thistleCarduus acanthoides L.25Poison hemlockConium maculatum L.26PuncturevineTribulus terrestris L.27Purple loosetrifeLythrum salicaria L.28Rush skeletonweedChondrilla juncea L.29Russian knapweedAcroptilon repens (L.) DC.; Centaurea repens L.30Russian thistleSalsola tragus L.; Salsola kali L.; Salsola iberica Sennen & Pau31Saltcedar/tamariskTamarix ramosissima Ledeb.Scotch broomCytisus scoparius (L.) Link33, 34Scotch thistleOnopordum acanthium L.35Spotted knapweedCentaurea bierbersteinii DC.; Centaurea maculosa Lam.; Centaureastoebe L. ssp. micranthos (Gugler) Hayek36St. JohnswortHypericum perforatum L.Sulfur cinquefoilPotentilla recta L.39Viper’s buglossEchium vulgare L.40White bryonyBryonia alba L.Yellow starthistleCentaurea solstitialis L.42, 43Yellow toadflaxLinaria vulgaris P. Miller4413, 141516, 173237, 38412
Index of Invasive Plants by Flower ColorCommon NameScientific NamePagesWhiteDiffuse knapweedCentaurea diffusa Lam.12Hoary cressCardaria draba (L.) Desv.; Lepidium draba L.13, 14Japanese knotweed; giant knotweed;Bohemian knotweedPolygonum cuspidatum Siebold & Zucc.; Fallopia sachalinensis(F. Schmidt ex Maxim.) Ronse Decr.; Polygonum x bohemicum(J. Chrtek & Chrtkovß) Zika & Jacobson16, 17Oxeye daisyLeucanthemum vulgare Lam.23Perennial pepperweedLepidium latifolium L.24Poison hemlockConium maculatum L.26Black henbaneHyoscyamus niger L.5Common groundselSenecio vulgaris L.8Common tansyTanecetum vulgare L.9Dalmatian toadflaxLinaria dalmatica (L.) Mill.Leafy spurgeEuphorbia esula L.19Meadow hawkweedHieracium caespitosum Dumort20PuncturevineTribulus terrestris L.27Rush skeletonweedChondrilla juncea L.Scotch broomCytisus scoparius (L.) Link33, 34St. JohnswortHypericum perforatum L.37, 38Sulfur cinquefoilPotentilla recta L.White bryonyBryonia alba L.Yellow starthistleCentaurea solstitialis L.42, 43Yellow toadflaxLinaria vulgaris P. Miller44Hieracium aurantiacum L.22Musk thistleCarduus nutans L.21Plumeless thistleCarduus acanthoides L.25Russian knapweedAcroptilon repens (L.) DC.; Centaurea repens L.30Saltcedar/tamariskTamarix ramosissima Ledeb.32Spotted knapweedCentaurea bierbersteinii DC.; Centaurea maculosa Lam.; Centaureastoebe L. ssp. micranthos (Gugler) Hayek36Cirsium arvense (L.) Scop.6Yellow10, 11293941OrangeOrange hawkweedPink to PurplePurpleCanada thistleHoundstongueCynoglossum officinale L.15Purple loosetrifeLythrum salicaria L.28Scotch thistleOnopordum acanthium L.35Blue/PurpleCommon buglossAnchusa officinalis L.7Viper’s buglossEchium vulgare L.40KochiaKochia scoparia (L.) Schrad18Russian thistleSalsola tragus L.; Salsola kali L.; Salsola iberica Sennen & Pau31Inconspicuous flowers3
Black HenbaneSolanaceaeHyoscyamus Niger L. NightshadeDescription:Historically,black henbanehas been usedmedicinallyand as anornamental. Itis an annual orbiennial plantthat reproduces Map of Washington State distribution.Plants Database.solely by seed.The plant formslarge rosettes with alternate, serrated leaves, anddevelops a fleshy taproot. Mature plants growup to 3 feet tall. The stems of a mature plantare erect, thick, coarse to tough, and widelybranched. Black henbane has abundant, foulsmelling foliage that is covered with fine, stickyhairs. The leaves are alternate, oblong to ovate,and coarsely toothed to shallowly lobed. Flowerscan be seen from spring to early fall. The flowersare funnel-shaped, 5-lobed, yellowish withdeep purple veins and throats, and arranged inspike-like clusters. The fruit is pineapple-shaped,approximately 1 inch long, with capsules thatcontain hundreds of tiny, dark seeds. A singleplant can produce up to a half million seeds thatare highly germinable and remain viable in thesoil for several years. Black henbane is commonlyfound in rangeland, pastures, roadsides, andwaste areas. The plant contains alkaloids thatcan cause livestock poisoning, although it isunpalatable and therefore seldom grazed. Itis largely considered poisonous to humans,but some people still value it for medicinalproperties.Flowers. Jan Samanek, State PhytosanitaryAdministration, Bugwood.orgCommon Names:insane root, stinking nightshade, fetidnightshade, hog’s beam, hogbean, hogbane,poison tobaccoOrigin: EuropeSeedlings. Jan Samanek, StatePhytosanitary Administration,Bugwood.orgRosette. Jan Samanek, StatePhytosanitary Administration,Bugwood.orgManagement:Efforts to control black henbane should be timedto precede seed production. Small infestationsof black henbane plants can be pulled, cut, ordug. Moist soil helps to remove the entire taproot system. Any seedpods should be baggedand removed from the site to avoid further seeddispersal. Mechanical methods, such as mowing,can be difficult if the plant is mature becauseof its thick, coarse stem. Herbicides can provideexcellent control and should be applied at therosette to bolt stage, but before flowering. Nobiological insect agents are currently available forcontrol of black henbane.Flowers and seed capsules. SteveDewey, Utah State University,Bugwood.org5
Canada thistle AsteraceaeCirsium arvense (L.) Scop.SunflowerDescription:Canada thistleis a dioeciousherbaceousperennialthat spreadsprimarily byan extensive,rhizomatousroot systemMap of Washington State distribution.Plants Database.that gives riseto numerousaerial shoots. Mature plants can grow up to 5feet tall. The stems are slender, ridged, branched,and somewhat hairy at maturity. The leaves arealternate, lance-shaped, and irregularly lobedwith spiny, toothed margins. Purple to whiteflowers surrounded by spineless bracts appearbetween June and October and occur in clustersat branch ends. The small, slightly tapered fruit(achene) has a feathery pappus that enables winddispersal. The seeds are abundant and can remainviable in the soil for 20 years. Canada thistle is anaggressive invader of a variety of open habitatsand can form dense stands that shade out anddisplace desirable vegetation. Canada thistle canresult in reduced forage, as its spiny leaves renderit unpalatable to most livestock.Purple and rare white flowers. Steve Dewey, Utah StateUniversity, Bugwood.orgCommon Names:Canadian thistle, creeping thistle, fieldthistle, small‑flower thistleOrigin:Europe and AsiaManagement:Seedling (young rosette). PhilWestra, Colorado State University,Bugwood.orgFoliage. Leslie J. Mehrhoff,University of Connecticut,Bugwood.orgInfestation. Steve Dewey, UtahState University, Bugwood.orgCeutorhynchus litura adult andlarvae. Noah Poritz,Bio-control.comBecause many thistle species exist in NorthAmerica, Canada thistle should be accuratelyidentified before control is attempted. Inmanaging the plant, control practices are mosteffective when combined. Regular tillage andplanting of competitive crops can keep Canadathistle in check, although tillage also producesroot fragments, giving rise to new plants.Repetitive mowing before seed set—preferably atearly bud stage when food reserves are at theirlowest—will weaken the plants and prevent seedproduction. Several herbicides are available foreither targeted or broad application, dependingon the presence of desirable vegetation. Repeatedapplications are often necessary. Biologicalcontrol agents include the stem-boring weevilCeutorhynchus litura and the thistle stem gallfly Urophora cardui. Though neither insect willkill plants outright, both can reduce Canadathistle populations over time, particularly inconjunction with good plant competition. Sheep,goats, and some cattle have been known tograze Canada thistle and provide some control;however, other control measures should also beused.Urophora cardui. Norman E.Rees, USDA Agricultural ResearchService, Bugwood.org6
Common buglossAnchusa officinalis L.BoraginaceaeBorageDescription:Commonbugloss is adeep-rootedperennial thatspreads by seed.A rosette appearsthe first year,followed by aflowering stalkMap of Washington State distribution.the second year. Washington State Dept. of Agriculture.Mature plantscan have multiple flower stalks. The stems arerobust, hairy, and grow to 2 feet tall at maturity.Leaves are lance-shaped, fleshy, and covered withstiff hairs. Basal leaves have a leaf stalk (petiole)that becomes progressively smaller up the stemto a point where the upper leaves are sessile (nopetiole). The flower stems start out coiled likea fiddleneck, but unfold and straighten out aseach flower bud opens. Purplish-blue, 5-lobedflowers appear from straight tubes rather thanthe curved tubes of annual bugloss. The fruit isa 4-chambered nutlet, with 1 seed per nutlet. Amature plant can produce up to 1,000 seeds in asingle season. Common bugloss invades alfalfafields, pastures, rangeland, and disturbed areas.Its succulent leaves and stalks can cause mold inbaled hay.Flower. Richard Old, XID Services, Inc., Bugwood.orgCommon names:common anchusa, alkanet, blue buglossOrigin:EuropeManagement:Cultural control will not eliminate commonbugloss populations. To gain control of commonbugloss, seed production must be prevented, sopulling, digging, or cultivating should take placebefore flowering. Removing most of the taprootimproves the effectiveness of these methods.Herbicides can be used and are most effectivewhen applied early, particularly before bud stage,and should include a surfactant to help penetratethe hairy leaf surface. Biological control agentsare not available for common bugloss.Rosette. Richard Old, XID Services,Inc., Bugwood.org7
Common groundsel AsteraceaeSenecio vulgaris L.SunflowerDescription:Common groundsel is usually a winter annual,but can also be biennial and grow in all seasonsdepending on climate. The plant has a taprootwith a fibrous root system, and grows upright,branched, and up to 18 inches tall. Basal leavesare usually purplish on the underside, somewhatfleshy, and attach to the stem with a shortstalk. The stem leaves clasp at the base and arealternate, mostly hairless, and pinnately dividedor irregularly toothed. Flower heads composedof small yellow disk flowers but no ray flowers(petals) occur in clusters at stem ends and havedistinct black-tipped bracts around the base.The seeds are abundant, long, slender, ridged,and when mature, are tipped with a tuft of silkywhite hairs (pappus) that aid wind dispersal. Theplant contains 4 pyrrolizidine alkaloids, whichcan cause irreversible liver damage in livestockif consumed in sufficient quantity. Commongroundsel is found in disturbed sites alongroadsides, waste areas, cultivated fields, andgardens.Flowers/fruit. Richard Old, XID Services, Inc., Bugwood.orgCommon names:old-man-in-the-spring, ragwort, grimselOrigin:EuropeManagement:Good management practices that promotecompetitive plant growth can reduce groundsel.Because of the plant’s prolific seed production,common groundsel is best controlled byeliminating it before it has a chance to flower.Monitoring for seedlings should begin in earlyfall. Shallow tilling or hoeing of young plants willcontrol the plant if done before seed set. Whileherbicides are not very effective for commongroundsel infestations in alfalfa and otherlegumes, they can be effectively used in othercrops. Despite the plant’s toxicity, sheep andgoats are sometimes used to graze it since theyhave rumen bacteria that detoxify the alkaloids.Larvae of the cinnabar moth Tyria jacobaeae willeat groundsel, but are not around long enoughto provide control. The rust fungus Puccinialagenophorae is showing promise as a biologicalcontrol agent, and is being further researched.Flower. Steve Dewey, Utah StateUniversity, Bugwood.orgRosette. Lynn Sosnoskie, Universityof Georgia, Bugwood.org8
Common tansy AsteraceaeTanecetum vulgare L.SunflowerDescription:Common tansy,a pungentsmellingperennial herb,was broughtto the UnitedStates forhorticulturaland medicinalMap of Washington State distribution.Plants Database.purposes. Theplant reproducesboth by seed and creeping roots. Stems areerect, brown or purplish-red, and dotted withglands. Mature plants grow from 2–6 feet tall.Fern-like leaves are alternate and deeply dividedinto numerous, individual leaflets with toothedmargins. Flowering occurs from July to the fall,varying by location. The yellow and button-likeflowers without ray florets appear in dense, flattopped clusters at the top of the plant. The seedsare yellowish-brown, 5-angled achenes, withno pappus. Common tansy is distinguishablefrom tansy ragwort (Senecio jacobaea), which isnon-aromatic and has ray florets and seeds withpappus. Common tansy plants invade disturbedareas, pastures, ditch banks, and riparian areas.This prolific plant contains alkaloids and ispotentially toxic to humans and most animals.Cattle and horses seldom graze the pungentplant, allowing common tansy to outcompetedesirable pasture plants.Flowers. Michael Shepard, USDA Forest Service, Bugwood.orgCommon names:garden tansy, golden buttonsOrigin:EurasiaPlant. Richard Old, XID Services,Inc., Bugwood.orgFlower. Steve Dewey, Utah StateUniversity, Bugwood.orgManagement:As with other rhizomatous perennials, acombination of control measures is most effectivein managing common tansy. Small infestationsof common tansy can be hand-dug, but theentire root system must be removed since plantscan resprout from severed roots. Gloves andother protective clothing should be worn toprevent absorption of toxins through the skin.Although tillage can produce root pieces thatresult in new plants, common tansy does notpersist in regularly cultivated lands. Repetitivemowing before the flowering stage can preventseed production, but other measures (such aschemicals) should also be used to achieve control.Numerous herbicides are available to managecommon tansy. Applications made between thebud and bloom stages tend to provide the bestresults. No insect biological control agents arecurrently available, although research is ongoing.Sheep and goats can be used to graze commontansy.Infestation. Steve Dewey, UtahState University, Bugwood.org9
Dalmatian toadflaxLinaria dalmatica (L.) oadflax isan attractiveherbaceousplant thatwas likelyintroducedto NorthAmerica as anMap of Washington State distribution.Washington State Dept. of Agriculture.ornamental.It is a shortlived perennial that reproduces both by seedand rootstocks. Dalmatian toadflax has taprootsand a creeping root system, reaching depths upto 10 feet and extending laterally up to 10 feetfrom the parent plant. New plants can formvegetatively from adventitious buds on thehorizontal roots, as well as from root fragmentsas small as ½ inch. The plant grows 1–3 feet tall.The stems are woody at the base, but becomesmooth, waxy, and often branching toward thetop. Waxy, light green to bluish-green leaves arebroad, ovate to heart-shaped, and clasp the stem.Dalmatian toadflax flowers, resembling those ofa snapdragon, are bright yellow and 2-lipped,with an orange-bearded throat and long spur.The flowers occur individually in a long, dense,terminal cluster and mature from the lower partof the stem upwards. During a single season, aplant can produce half a million seeds that canremain viable for 10 years. The seeds, producedin a 2-celled capsule, are irregularly-shaped,sharply angular, slightly winged, and darkcolored. Dalmatian toadflax contains a poisonousglucoside, but reports of livestock poisoning arerare because the plant is unpalatable. Dalmatiantoadflax is an aggressive colonizer that invadesdisturbed sites, including roadsides, clear cuts,rangelands, and croplands. It can outcompetedesirable species and significantly reduce forage.Plant. Utah State University Archive, Utah State University,Bugwood.orgCommon names:broadleaf toadflax, wild snapdragon, butterand eggsOrigin: Mediterranean regions of Europe toCentral AsiaFlower. Bob Nowierski, MontanaState University, Bugwood.orgNonflowering, prostrateDalmatian toadflax shootsproduced mid- to late summer.Linda Wilson, University of Idaho,Bugwood.orgManagement:Control strategies should be aimed at preventingseed production, depleting root reserves, andeliminating seedlings before they can propagatevegetatively. Cultu
Invasive Weeds of Eastern Washington Stephen M. Van Vleet, Ph.D. Washington State University Whitman County Extension Introduction The rapid spread of invasive plants threatens natural resources across the United States, and the Pacific Northwest is no exception. Invasive species displace natural plant communities and have the following impacts:
A coloring book with original drawings and educational information about noxious weeds found in King County, Washington Keywords: coloring, coloring book, noxious weeds, school, weeds, invasive species, king county, washington, Karen Peterson, art, student, kids, children, educational activities Created Date: 3/27/2020 3:23:34 PM
the introduction and establishment of weeds. 1: Prevention is key 2: Increase natural weed mortality 3: Use cultural methods to put weeds at a disadvantage 4: Keep weeds off balance 5: Use as many "little hammers" as possible 1) Prevention is key. Limit seed introduction, production, and dispersal. Identify weeds and take appropriate action.
Invasive species (weed) control is a required component of sound . range and pasture management, with many producers perceiving . that control or removal of weeds equates to range health and thus . additional profit potential. Further, control of a certain group of exotic invasive species known as 'noxious weeds' demands control
Invasive Exotic Plant - An aggressive plant that is known to displace native plant species. Invasive exotic species are unwanted plants which are harmful or destructive to man or other organisms (Holmes, 1979; Webster). State Listed Noxious Weeds – Invasive exotic plants prohibited or restricted by Colorado Law.
“weeds.” To most these weeds are unsightly, a nuisance, and they serve no purpose. We see weeds as plants that rob us of production potential. I would suggest though that not all weeds are wicked. There are many definitions for the word weed. They can be a plant out of place, an unwanted plant, or a plant that interferes with production.
moss & algae (Table 9, Table 14 – p5, Table 15 – p5). A more detailed look at the weeds respondents included in the survey is warranted (Table 16 - p5). The top weeds mentioned were nutsedge and liverwort. Four broadleaf weeds were included frequently: thistle, bittercress, spurge, and oxalis. Table 9. Ranking of weeds with limited
Integrated Weed Management Biological Weed Control for Colorado Landowners If more than 80% of the pasture is weeds, consider reseeding (see Figure 2). No You are managing weeds well. Continue routine scouting and managing of weeds. Figure 2: More than 80% of this pasture is weeds. Kochia, Russian thistle, and cheat
Grade 2 ELA Standards, Clarifications and Glossary 2 GRADE 2 READING STRAND: K-12 Standards for Reading define what students should understand and be able to do by the end of each grade. Students should demonstrate their proficiency of these standards both orally and through writing. For students to be college and
