A weed management area group was formed for Marin and Sonoma Counties in early 1999. The Weed Management Area's (WMA) plan is to unite individual ownership and public agencies, provide an opportunity to share resources in mapping, planning information and help control weeds across land ownership boundaries. The WMA has performed a number of weed control projects.

The State Legislature (AB 1168 & SB 1740) authorized funding to weed management areas. With this funding, the WMA hired a hand pulling weed crew to remove wooly distaff thistle (Carthamus lanatus), purple star thistle (Centaurea calcitrapa), and yellow star thistle (Centaurea solstitialis). The WMA works with all landowners to determine the best method of control of each individual landowner's requirements. Both mechanical and chemical removal of weeds is utilized.

In 2008, the MSWMA received over $33,000 from the California Department of Food and Agriculture for the development of a Rapid Response Program for 2009. The program is designed to address early infestations of invasive weeds before they spread to larger areas and require costly control methods, or become completely uncontrollable. Under this funding, Noelle Johnson of the Gold Ridge Resource Conservation District, a partner organization, has assumed the role of Rapid Response Coordinator, and is working to collect information on early infestations throughout Marin and Sonoma counties.

A website is being developed to allow Weed Management Area (WMA) partners, landowners, and the general public to report early invaders, stay informed about WMA activities, and follow links about invasive weeds and control methods. Please visit http://marinsonomaweedmanagement.org/ or contact the Rapid Response Program at Noelle@goldridgercd.org for more information. Information about the larger Bay Area Early Detection Network can be found at: http://www.baedn.org/

Some priority weed occurrences occur on private lands. The Rapid Response/Bay Area Early Detection Network ensures that these habitats are not left out of the solution, and also connects the MSWMA with ranchers, farmers, and private landowners.