Presidio Trust to Improve Habitat for Rare Grasslands

Presidio of San Francisco (July 11, 2007) —The Presidio Trust and National Park Service are testing methods this summer and fall to improve habitat for one of California’s rarest plant communities, serpentine prairie grasslands. Some of the last remaining serpentine prairie exists in fragments over a 15-acre area at the Presidio’s Inspiration Point.

“The purpose of the pilot project is to increase the population of Presidio Clarkia and to create environmental conditions favorable for the reintroduction of Marin dwarf flax seed to the site” said Mark Frey, Presidio Trust Ecologist. “The remnant grassland at Inspiration Point is fragmented due to plantation of non-native trees and invasion of annual and perennial non-native grasses.”

Trust and National Park Service natural resources staff will test several methods for controlling exotic plants at the site, including: mowing, scraping, tarping and fire control. These treatments are being applied to eighty-one 1 x 1 meter test plots, creating a “patchwork quilt” effect that will allow scientists to determine which approach works best.

The fire treatment is being applied to 27 plots in both spring and fall, when conditions are right. Fire crews must get permission from the Bay Area Air Quality Management District before igniting a controlled burn. The plots are being burned within a tall, portable metal box which will prevent fire from spreading outside of the test area. National Park Service Wildland Fire Crews will be on-site managing the burns.

“The goal of the controlled burn is to test the effect of fire in relation to other treatments for improving Presidio Clarkia habitat,” said Lewis Stringer, the project organizer. “It may be that there is no difference between this method and other treatments, but we need to study it before we can make that determination.” Stringer is a Natural Resource Management Specialist for the National Park Service, Golden Gate National Recreation Area.

In August, 2007, a small stand of aging Monterey pine trees will be removed to expand habitat in the west grassland.

Created by Congress in 1996, the Presidio Trust is charged with preserving the Presidio’s natural, historic and scenic resources while making the park financially self-sufficient by 2013. Natural resources staff from the Presidio Trust and National Park Service work closely to enhance and protect the Presidio’s native plants and wildlife.