Surveying the Mt. Tamalpais Watershed

We’re working with the Marin Municipal Water District (MMWD) to document and collect every known plant species on the more than 18,000 acres it manages. The MMWD takes care of its watershed lands not only to provide clean drinking water to Marin residents, but also to protect the incredible biodiversity of the area. Though the watershed makes up only .01 percent of the land in California, 15 percent of the state’s flora is found there, including eight species found only in Marin.

This citizen science inventory of plants found in the watershed will provide the MMWD with a comprehensive baseline with which to track future change; it will also yield much-needed information about currently threatened, endangered, and non-native species. By the beginning of 2014—the third year of the project—our citizen scientists had already documented more than 600 of the 900-plus known species.