Invasive Spartina Removal and Tidal Marsh Restoration Project

California Invasive Plant Council (Cal-IPC)
Planting native plans after invasive removal

Counties of Marin, Sonoma, Napa, Solano, Alameda, Contra Costa, San Mateo, Santa Clara, and San Francisco

Measure AA Program Category:

Vital Fish, Bird and Wildlife Habitat Program.


State Coastal Conservancy (SCC) and the United States Fish and Wildlife Service (USFWS), among many others


2023 UDPATE:  Mapping and treatment field work occurred June 2022 through January 2023, covering 216 sub-areas and 70,000 acres. During the 2022 treatment season, the project team also monitored Ridgway's rail at 120 sites, and planted ~20,000 native marsh plants at 12 sites in winter 22-23. As of 2022 monitoring, the project has reduced invasive Spartina in all nine bay counties by 97% to a total of 20.5 net acres baywide. Lead grantee CA Invasive Plant Council also planned and led more than 10 public outreach presentations and six workforce development trainings from Spring 2022-Spring 2023. Match grant funding is provided by the State Coastal Conservancy and USFWS National Coastal Wetlands Program. 


2022 UPDATE: During FY2021-2022, in addition to continued efforts to monitor and treat invasive Spartina, project partners propagated and outplanted 21,000 plants at several sites around the Bay and the grantee planned and led more than 10 public outreach presentations. Quality control occurred on all 2021 season monitoring data in Spring 2022, along with planning for June 2022-January 2023 season. 

This grant supports the continued eradication of invasive cordgrass (invasive Spartina) and enhancement of critically important tidal marsh and mudflat habitat throughout the entire nine county San Francisco Estuary. The project includes invasive Spartina monitoring and treatment, native marsh plant revegetation, California Ridgway’s rail (rail) monitoring, and community outreach and job training in partnership with the long-term Invasive Spartina Project (ISP) led by the State Coastal Conservancy (SCC) and the United States Fish and Wildlife Service (USFWS) as the state and federal leads.

Pacific cordgrass (native Spartina) is an important native species in the Estuary’s tidal marshes and mudflats as the primary plant that naturally occurs at the low intertidal zone between bay waters and tidal marsh edge. Pacific cordgrass contributes to the base of the food chain in the bay and provides critical habitat where a variety of species hide from predators, forage, and nest. Atlantic cordgrass (invasive Spartina), native to the East Coast, was introduced by the Army Corps of Engineers in the early 1970’s and subsequently hybridized with the native Spartina.

Invasive Spartina invades both tidal mudflats and marshes and scientists have documented changes in the physical structure and plant communities in these habitats, and the resulting degradation of biodiversity and habitat values for native species. The ISP is a successful regionwide collaborative effort to eradicate invasive Spartina that was started in 2000 by the SCC and USFWS. The ISP engages a network of more than 150 partners, including Cal-IPC, local, state, and federal resource agencies, non-profit organizations, local small business contractors, universities, environmental consultants, and landowners to implement the project.

This coordinated regional project is critical to the protection of native tidal marsh restoration throughout the Estuary, due to concerns of rapid and aggressive spread of the invasive species and alteration of native tidal marsh and mudflat habitats. The ISP has also been successful in securing local, state, and federal funding for continuous treatment and, as of 2019, the project has reduced the net acreage of invasive Spartina by 95%, from the high of 805 net acres in 2005 down to 38 net acres in 2019).

The ISP also includes a revegetation program to propagate and outplant native marsh plants such as Pacific cordgrass (Spartina foliosa) and marsh gumplant (Grindelia stricta). Both of these native marsh species will provide needed habitat for wildlife in the near-term and will serve as seed sources for further spread throughout nearby marshes. Both species provide nesting substrate for rails, and gumplant in particular is at a higher tidal elevation and provides the vertical structure necessary for high tide refuge.