News Releases

OLYMPIA – This year’s treatment season for Spartina, an aggressive invasive cordgrass weed, starts June 1 and will continue through November.

Washington State Department of Agriculture (WSDA)-led survey and eradication efforts for Spartina will take place in multiple areas, including Grays Harbor, Hood Canal, Willapa Bay, the Puget Sound, the north and west sides of the Olympic Peninsula, the San Juan Islands and near the mouth of the Columbia River.

This year, crews will address the trend of Spartina spreading into and impacting important restoration projects in the north Puget Sound. Since 1995, WSDA has served as the lead state agency for Spartina eradication, facilitating the cooperation of local, state, federal and tribal governments; universities; interested groups and private landowners. This cooperative effort located and treated over 21,000 individual Spartina plants last year.

WSDA’s collaborative Spartina eradication effort has been highly effective — reducing infestations from a high of more than 9,000 total acres in 2003 to 6.7 total acres in 2024. The effort has successfully eradicated Spartina at 76 sites, however significant work remains to be done. The remaining 6.7 acres are spread over 126 sites — meaning 62 percent of Washington’s 202 infestations are not yet eradicated.

“Our goal is to eradicate Washington’s remaining Spartina infestations, protecting important habitat for salmon, waterfowl and shellfish,” said Chad Phillips, WSDA’s Spartina Program Coordinator. “The Spartina eradication program protects our state’s most productive estuaries and shoreline habitats. This year, with our project partners, we will continue the challenging work of finding and removing the thousands of Spartina plants that remain in the Puget Sound and along Washington’s coast.”

This season, the project partners will survey thousands of acres of saltwater estuaries and hundreds of miles of shoreline. WSDA and its partners typically dig out small infestations by hand and utilize herbicides at larger sites.

Eradication is vital to protect Washington’s valuable restoration projects, shorelines and ecosystems. If not eradicated, Spartina will reinfest the estuaries and shoreline previously returned to productive habitat through years of consistent Spartina removal.

Commonly known as cordgrass, Spartina can disrupt the ecosystems of native saltwater estuaries. It outcompetes native vegetation and converts ecologically healthy mudflats and estuaries into solid Spartina monocultures. As a result, important habitat for salmon, forage fish, invertebrates, shorebirds and waterfowl are lost, the threat of flooding increases and the state’s shellfish industry is negatively impacted.

Visit agr.wa.gov to for more information on Spartina control efforts.