INTRODUCTION: The Umatilla County Weed Control Board and Board of County Commissioners believes that the prevention and eradication of newly invading weed species yields the greatest return for the resource investment. This is best achieved through an intensive survey and inventory program allowing for early detection and early action. Education and awareness is an integral part of prevention and early detection. Being familiar with what is growing around us is the best way to assure that when a new invader arrives, it will be noticed and dealt with at the most effective stage of development.


Per ORS.569.350-569.520 the following lists is 2017 adopted Umatilla County Noxious Weed Control List. The weeds listed here are those on the 2017 Umatilla County list (this list was recommended by the Umatilla County Weed Board and approved by the Umatilla County Board of Commissors) CURRENTLY FOUND GROWING OR KNOWN TO HAVE GROWN PREVIOUSLY in Umatilla Co. They are divided according to control requirements categories "A" and "B"

“A” designated weed-a weed of known economic importance which occurs in the state/county in small enough infestations to make eradication/containment possible; or is not known to occur, but its presence in neighboring states/county make future occurrence in Oregon seem imminent.

“B” Designated weed-a weed of known economic importance which is regionally abundant, but which may have limited distribution in some counties. Where implementation of a fully integrated statewide management plan is feasible, biological control shall be the main control approach for species which biological agents are available; noted by asterisk.

"A" Designated Weed List

These Class “A” weeds have been found as single plants or in very limited populations in the county. Prevention, early detection, and eradication is high priority. Cost share may be available at the Weed Board discretion

  • Camelthorn (Alhagi pseudalhagi)
  • Common Bugloss (Anchusa officinalis)
  • Common Crupina (Cupina vulgaris)
  • Creeping Yellow Cress (Roripa sylvestris)
  • Flowering Rush (Botomus umbellatus)
  • Garlic Mustard (Alliaria petiolata)
  • Japanese Knotweeds [fleece flower] (Polygonum cuspidatum [Fallopia japonica])
  • Leafy Spurge (Euphorbia esula)
  • Marijuana (Cannabis sativa)
  • Meadow Knapweed (Centaurea jacea XC. Nigra)
  • Myrtyle Spurge (Euphorbia myrsinites)
  • Purple Loosestrife (Lythrum salicaria)
  • Purple Starthistle (Centaurea calcitrapa)
  • Rush Skeletonweed (Chondrilla juncea)
  • Spike Weed (Hemizonia pungens)
  • Spotted Knapweed (Centaurea maculosa)
  • Tansy ragwort (Senecio jacobaea)
  • Viper’s bugloss (Echiuin vulgare)
  • Yellow flag iris (Iris pseudacorus)

RECOMMENDED ACTION: Infestations are subject to intensive control when and where found.

"B" Designated Weed List

RECOMMENDED ACTION: Limited to intensive control at state or county level as determined on a case-by case basis.

  • Austrian Peaweed (Sphaerophysa salsula)
  • Canada Thistle (Circium arvense)
  • Cereal Rye (Secale cereale)
  • Dalmation Toadflax (Linaria dalmatica)
  • Dodder (Cuscuta pentagona)
  • Diffuse Knapweed (Cuscuta pentagona)
  • Hoary Cress (Cardaria draba)
  • Johnsongrass (Sorghum halepense)
  • Jointed Goatgrass (Aegilopscylindrica)
  • Kochia (Kochia scoparia)
  • Mediterranean Sage (Salvia aethiopis)
  • Musk Thistle (Carduus nutans)
  • Puncturevine (Tribulus terrestris)
  • Poison hemlock (Coium maculatum)
  • Quackgrass (Agropyron repens)
  • Ragweed (Ambrosia artemisiifolia)
  • Russian Knapweed (Acroptilion repens)
  • Scotch Thistle (Onopordum acanthium)
  • St. Johswort (Hypericum perforatum)
  • Yellow Starthistle (Centaurea solstitialis)

Enforcement emphasis groups; these groups of invasive plants have been targeted for additional enforcement throughout the County according to the land types and corresponding agricultural uses associated. Three land uses types have been identified and weed lists developed for each they are:

  • Dry Land Annual Cropping Areas: Emphasis Weeds, Canada Thistle, Scotch Thistle, Yellow Starthistle, Goatgrass, and Kochia.
  • Irrigated Crops and Pastures: Emphasis Weeds, Canada Thistle, Scotch Thistle, Bull Thistle, Musk Thistle, Yellow Starthistle, Diffuse Knapweed.
  • Dryland Range/Pasture/Timber: Scotch Thistle, Bull Thistle, Canada Thistle Spotted Knapweed, Diffuse Knapweed, Russian Knapweed.