
Scotch broom is one of the most costly invasive species in Washington, according to a 2017 report commissioned by Washington State agencies. Of the 23 species analyzed, the study found that Scotch broom is near the top of the list in terms of economic impact on Washington’s landscapes, agriculture, business, and recreation.
Scotch broom is a serious threat to native prairies and forests, it prevents timber regeneration, and it displaces pasture forage for grazing animals. As if that wasn’t bad enough, the plant is also toxic to livestock and creates a fire hazard due to its high flammability. According to the report, if Scotch broom is allowed to spread an additional 12 percent a year in Washington, it has the potential total economic impact of $142.7 million and the loss of 660 jobs.
On May 23, a consortium of Scotch broom researchers will be presenting the latest information on Scotch broom at a free symposium being held at the Snoqualmie Casino in Snoqualmie, Washington. The researcher’s information will be useful for addressing and mitigating Scotch broom’s impacts to Washington’s economy and natural resources.

Topics include research on soil legacy effects, seed banks, pollinators, suppression through logging slash, and impacts to a wide variety of landscapes. Researchers and applied scientists will also convey best management practices for control and restoration, including herbicide use, mechanical control, biocontrol, and use of prescribed fire.
This workshop is hosted by the Snoqualmie Tribe Environmental and Natural Resources Department, in partnership with the Washington Scotch Broom Working Group, 10,000 Years Institute, University of California Santa Cruz, Northern Arizona University, Washington Invasive Species Council, Washington State Noxious Weed Control Board, Washington State Department of Agriculture, Washington State Department of Transportation, King County Noxious Weed Control Program, King County Noxious Weed Control Program, and National Science Foundation. Six pesticide applicator recertification credits have been applied for in the States of Washington and Oregon.
To learn more and register, visit http://www.invasivespecies.wa.gov/scotch-broom-symposium.shtml. There is no cost to attend, but pre-registration is required.