Sherman County Soil and Water Conservation District

“C” CLASS – LOW PRIORITY. A noxious weed which is wide spread throughout the County and has known economic impacts.

Bull Thistle, Cirsium vulgare

Common Rye, Secale cereale

Field Dodder, Cuscuta campestris

Jointed Goatgrass, Aegilops cylindrical

Klamath Weed (St. Johnswort), Hypericum perforatum

Little Bur (Bur Buttercup), Ranunculus testiculatus

Marestail, Contza Canadensis

Medusahead Rye, Taeniatherum caput-medusae

Perennial Pepperweed, Lepidium latifolium

Poison Hemlock, Conium macalatum

Prickly Lettuce, Lactuca serriola

Puncturevine, Triulus terrestris

Quackgrass, Elytrigia repens

Russian Thistle, Salsola iberica

Spiny Cockelbur, Xanthium spinosum

Waterhemlock, Western Cicuta douglasii

Wavyleaf Thistle, Cirsium undulatum
“A” CLASS – HIGH PRIORITY. Any noxious weed which greatly endangers the overall economic well-being of the County and has a small enough distribution where eradication is possible.

Canada Thistle,  Cirsium arvense

Houndstounge, Cynoglossum officinale L.

Jimsonweed, Datura stramonium

Kochia, Kochia scoparia

Leafy Spurge, Euphorbia esula

Knapweed Complex, Centaurea Species
    Diffuse Knapweed,  Centaurea diffusa
    Russian Knapweed, Rhaponticum repens
    Spotted Knapweed, Centaurea stoebe

Rush Skeletonweed, Chondrilla juncea

Spikeweed, Hemizonia pungens

Yellow Starthistle, Centaurea solstitialis


“B” CLASS – MODERATE PRIORITY. A noxious weed which is well established in the County and has known negative impacts, but due to its distribution, eradication is not feasible.

Canada Thistle, Cirsium arvense

Dalmation Toadflax, Linaria genistifolia-dalmatica

Field Bindweed (Morningglory), Convolvulus arvensis

Knapweed Complex, Centaurea Species 
    Diffuse Knapweed,  Centaurea diffusa
    Russian Knapweed, Rhaponticum repens
    Spotted Knapweed, Centaurea stoebe

Perennial Sowthistle, Sonchus arvensis

Scotch Thistle, Onopordum acanthium

Scouring Rush, Equisetum laevigatum

Showy Milkweed, Asclepias speciose

White Top (Hoary Cress), Cardaria draba

Wild Oat, Avena fayua

Yellow Starthistle, Centaurea solstitialis