This past winter, the Washington State Noxious Weed Board added Flowing Rush to our state’s noxious weed list as a Class A weed. Class A weeds are those that pose a severe threat to water resources and are not yet well distributed. The law requires their control where found. Today, our biologists spent the day canoeing Silver Lake in Whatcom County. This lake is one of the few known location of flowering rush in the state. The littoral zone of the lake was heavily impacted by this invasive species. We found it growing completely submerged at depths up to nine feet with plants reaching to the lake surface.
The Department of Ecology and the Whatcom County Noxious Weed Board will be conducting trials to select appropriate management tools this summer. A number of plots will be selected from the areas of dense growth and applications of Renovate OTF, Renovate MAX G and Clearcast Herbicide are expected to be applied to the growth. These technologies have worked well in laboratory work conducted in Montana.
For more information on this noxious weed, go to http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/weed-identification/flowering-rush.aspx