A photo of Scotch broom in Discovery Park in King County, Washington

Learn the latest on Scotch broom at symposium in Snoqualmie on May 23

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…

New forest invader called small-flowered jewelweed discovered on Novelty Hill Rd

King County weed specialists recently responded to a report of a new forest invader called small-flowered jewelweed found along Novelty Hill Rd just east of Redmond Ridge. This central Asian species is a widespread invasive plant in European forests, but is still highly localized in North America. According to a 2013 USDA-APHIS report, it is being…

It’s official – Washington bans sale of six new plants including yellow archangel, butterfly bush and lesser celandine

Effective July 24, the list of prohibited plants in Washington just grew by six. The species added include several popular ornamental plants that are now prohibited from sale: butterfly bush (non-sterile varieties), yellow archangel, lesser celandine and all hybrid non-native hawkweeds, including a type of orange hawkweed that was until very recently still being sold in…