Vegetation and Biodiversity Management

Reducing fire risk, controlling invasive species, and restoring native habitat on open space lands.

The Marin County Open Space District (MCOSD) manages 34 open space preserves with unique species and ecosystems. MCOSD strategically applies resources to reduce wildfire risk on county lands, especially in the wildland/urban interface where open space preserves border homes and neighborhoods. Measure A has allowed the MCOSD to significantly increase spending on vegetation management. As wildfires in California and the Bay Area have become more frequent and of greater intensity due to a warming climate, this work is more important than ever. MCOSD vegetation management goals:

  • Protect sensitive habitats
  • Reduce fire fuel hazards
  • Manage invasive plants
  • Provide safe and sustainable recreation opportunities

Crew removing fallen tree Sheep herder with grazing animals and herd dog Early Detection, Rapid Response team identifying invasive plant species Firefighters burning brush piles 


Since Marin voters passed Parks Measure A in 2012, vegetation and biodiversity management capabilities have been significantly expanded. Measure A provides funds to pay vegetation and fire ecology science staff, who identify, oversee, and monitor priority project areas. Measure A adds boots on the ground, by funding a Marin County Fire crew, Conservation Corps North Bay crews, and outside contracting services. It also supports bringing in substantial numbers of grazing animals seasonally. This provides additional tools to draw upon in the effort to reduce fire fuel, maintain emergency access, reduce invasive plant species, and support safe recreation in Marin County preserves.

  • MCOSD staff perform routine maintenance, such as mowing and removing hazards.
  • Conservation Corps North Bay (CCNB) assists on a variety of projects – clearing brush, weed whacking, and removing debris.
  • Sheep, goat, and cattle grazing are used strategically in different areas of county preserves.
  • Contracted service crews are hired as needed to work in high priority areas.
  • The Early Detection, Rapid Response team conducts surveys for invasive plants throughout all Marin County preserves.
  • In 2019 and 2020, a Marin County Fire crew funded by Measure A took on key vegetation projects.

Vegetation Management Open Data

MCOSD maintains information and visualizations about open space vegetation management, including the interactive work map below, on the County of Marin Open Data portal.


In March 2020, Marin voters funded the Marin Wildfire Prevention Authority (MWPA), a new agency to lead the development of fire adapted communities in Marin. The MCOSD engages in an ongoing collaboration with MWPA and Marin County Fire, as well as other regional fire agencies, to maximize the effectiveness of resources and establish vegetation management priorities.

Marin County Parks is a One Tam partner. Recent initiatives include the Marin County Vegetation Mapping and Land Cover Data site. Aerial imagery, QL1 lidar, topographic, vegetation, and other landcover data across Marin County is now available to support a variety of applications including vegetation management and monitoring, habitat modeling, change detection, fire and flood preparedness, and more. Data is available free for the county as whole, by watershed, or specific areas.

For questions about the Vegetation and Biodiversity Management program contact Vegetation and Fire Ecologist Sarah Minnick.