The nutrient poor serpentine grasslands at Edgewood Natural Preserve support the last remaining population of the threatened Bay checkerspot butterfly on the San Francisco Peninsula, along with a dazzling diversity of native wildflowers and bunchgrasses. The Edgewood population numbered in the thousands in the mid-1990's, but numbered less than 100 butterflies in 2000. A major cause of the decline has been invasion by introduced annual grasses that choke out the larval hostplants of the butterfly, an invasion that has progressed rapidly since 1993.

In March 2001, San Mateo County Parks and Recreation Foundation obtained a $70,000 NFWF grant to initiate habitat restoration studies at Edgewood Natural Preserve. Funding was provided for the period March 2001 to Oct. 2002. Grant activities included an inventory of current habitat conditions including aerial photography (color and IR), ground level transects, and small-scale restoration experiments such as prescribed fire, mowing, goat grazing, and seeding in larval hostplants.

This document serves as a final report on activities under the grant, and present a set of management recommendations for initiating long-term restoration of the serpentine grasslands.