Snoqualmie Valley forests at risk from aggressive invasive weed garlic mustard
April 23, 2010
NEW — 4:30 p.m. April 23, 2010
King County’s Noxious Weed Program is on high alert after an aggressive invasive plant was discovered in the agriculturally important Snoqualmie Valley.
Garlic mustard, a plant that crowds out native vegetation and depletes soil nutrients, was found growing on several adjacent properties in North Bend near a creek that drains into the South Fork Snoqualmie River. Like other noxious weeds, the plant is not native to the region and can cause ecological and economic damage.
It is the first confirmed infestation of garlic mustard in the Valley. Another infestation was found earlier in Bellevue near Cougar Mountain Regional Wildland Park.
King County and Bellevue officials are working to eradicate that outbreak.
Sasha Shaw, a noxious weed specialist with King County, said it’s possible the plant could have been introduced to the area in gravel dropped recently by a visitor from the Midwest.
“This forest invader is already a widespread problem across much of the eastern and midwestern United States, and it is on the move in the Pacific Northwest,” Shaw said.
Residents are being urged by the county to contact the Noxious Weed Program in its Water and Land Resources Division if they think they have found garlic mustard on their property or in their neighborhood.
“It can be hard to identify because it looks like a lot of other plants and weeds that grow out there in the woods,” said Doug Williams, spokesman for King County Department of Natural Resources and Parks.
At one point during its development, the plant produces a smell similar to garlic. Photos and descriptions of the plant are available on the county’s website.
The plant spreads by seeds. One stand can produce more than 62,000 seeds per square meter, quickly pushing out local flora and changing the make up of plant communities on the forest floor.
Visit the Noxious Weed Program website, www.kingcounty.gov/weeds, to see photos and descriptions of the plant, or call 206-296-0290.