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Help collect invasive ivy samples.

The State Noxious Weed Control Board is conducting a project in Washington to determine whether Atlantic ivy, Helix hibernica (commonly called English ivy), is still the more abundant species compared to English ivy, Hedera helix

Get involved by sending us invasive ivy samples for our project: click here to find out more.


Proposed changes for the 2018 Washington State Noxious Weed List

The State Weed Board welcomes your comments about the proposed changes to the 2018 state noxious weed list. The Board is considering: adding small-flowered jewelweed (Impatiens parviflora) as Class A noxious weed; adding Malta starthistle (Centaurea melitensis) and European coltsfoot (Tussilago farfara) as Class B noxious weeds; adding hybrid watermilfoil, a hybrid between Eurasian watermilfoil (Myriophyllum spicatum) and northern watermilfoil (Myriophyllum sibiricum), as a Class C noxious weed; adding spotted jewelweed (Impatiens capensis) and cheatgrass (Bromus tectorum) as Class C noxious weeds; reclassifying spurge flax (Thymelaea passerina) from a Class A noxious weed to a Class B noxious weed, to be designated for control in eastern Washington except for Okanogan County.

The Board is also considering the following Class B designation changes: undesignate shiny geranium (Geranium lucidum) and butterfly bush (Buddleja davidii) in Thurston County; undesignate Eurasian watermilfoil (Myriophyllum spicatum) and yellow nutsedge (Cyperus esculentus) in Clark County; and undesignate Eurasian watermilfoil in Cowlitz County; designate indigobush (Amorpha fruticosa) in Clark County, except within 200 feet of the ordinary high water mark of the Columbia River; designate policeman's helmet (Impatiens glandulifera) in Clark County; designate Eurasian watermilfoil in Kittitas County, except in the Columbia River.

You can submit written testimony regarding these proposed changes by email to noxiousweeds@agr.wa.gov or snail-mail letters to WSNWCB; P.O. Box 42560; Olympia, WA 98504-2560 by Monday, October 30, or you can attend our public hearing that starts at 1:00 p.m. at the Coast Conference Center in Wenatchee on October 31st.

More information is available in our press release--download the press release here.

View our CR-101 (WRS 17-14-032, published July 19, 2017), CR-102 (WRS 17-19-110, published October 4, 2017), OTS draft languageSBEIS Analysis

Impatiens Parviflora
Small-flowered jewelweed (Impatiens parviflora)

Download the written findings for small-flowered jewelweed, being considered as a Class A noxious weed for 2018.

A widespread invasive annual in Europe, two populations of small-flowered jewelweed were recently discovered in Washington.

Malta Starthistle
Malta starthistle (Centaurea melitensis)

Download the written findings for Malta starthistle, being considered as a Class B noxious weed for 2018.

Malta starthistle, an invasive annual in California and Oregon, was discovered last year in Skagit County, the first time found in the state since 1985. Similar in appearance to the noxious weed yellow starthistle, Malta starthistle is proposed as a Class B noxious weed with control being designated in the same counties as yellow starthistle: all of Washington except in Klickitat, Whitman, Benton, Franklin, Walla Walla, Columbia, Garfield, and Asotin counties, and a portion of Stevens County.

Tussilago Farfara
European coltsfoot (Tussilago farfara)

Download the written findings for European coltsfoot, being considered as a Class B noxious weed for 2018.

European coltsfoot is a rhizomatous perennial that thrives in disturbed environments. Currently with scattered populations in western Washington, European coltsfoot is proposed as a Class B noxious weed to be designated for control throughout Washington, except for in Grant, Lincoln, Adams, Benton, and Franklin counties.

Impatiens Capensis
Spotted jewelweed (Impatiens capensis)

Download the written findings for spotted jewelweed, being considered as a Class C noxious weed for 2018.

Found primarily in western Washington, spotted jewelweed thrives in wetlands, forests and riverbanks. Native to the central and eastern United States, plants are spreading successfully in Washington and are also able to hybridize with another Impatiens species, native Impatiens ecornuta, spurless jewelweed.

Eurasian Watermilfoil Hybrid
Eurasian watermilfoil hybrid (Myriophyllum spicatum x M. sibiricum)

Download the written findings for Eurasian watermilfoil hybrid, being considered as a Class C noxious weed for 2018.

This perennial hybrid, a cross between the invasive Eurasian watermilfoil (Myriophyllum spicatum) and the native northern watermilfoil (Myriophyllum sibiricum), can result in a variety of strains--some that are aggressive and resistant to some control treatments. Genetic testing is needed to confirm the identity of the hybrid due to overlapping traits with the parent species.

Bromus Tectorum
Cheatgrass (Bromus tectorum)

Download the abbreviated written findings for cheatgrass, also known as downy brome, being considered as a Class C noxious weed for 2018. Download the supplement document: Downy Brome (Bromus tectorum) and Japanese Brome (Bromus japonicus) Biology, Ecology, and Management, literature review by K. George Beck, which serves as the primary source of information for the written findings.

Cheatgrass, also commonly known as downy brome, is a common invasive annual grass that becomes fuel for fires once it dies back. Though it can be grazed when it is young, production is variable and the awns of the mature seeds can injure animals. Control is not required of Class C noxious weeds at the state level, rather the focus would be on educating about management, including areas impacted by wildfires.

Thymelaea Passerina
Spurge flax (Thymelaea passerina)

Download the written findings for spurge flax, being considered for reclassification from a Class A noxious weed to a Class B noxious weed for 2018.

Spurge flax has become too widespread in Okanogan county for eradication to be a reasonable requirement. If reclassified to a Class B noxious weed, control would be required throughout eastern Washington, except in Okanogan County.