COSCA Volunteer Corps: Resource Stewardship

This program offers volunteers the opportunity to participate in a wide variety of natural resource-related open space stewardship, management, and education projects such as non-native species control, invasive plant eradication, or the restoration of sensitive resource areas within COSCA’s open space system.

Non-native plants in our open space crowd out native grasses and other plants. Over time, these pest plants reduce the variety of native plant and animal life. To help keep this problem under control, volunteers can assist the park rangers in locating some of the most invasive of the non-native plants. With the information provided by volunteers, the rangers can better decide how to deal with and/or eliminate the non-native plants. At this point, volunteers are asked to help with locating three invasive, non-native species in the Conejo Open Space: sweet fennel, arundo, and palm trees.

See the current Volunteer Manual for a more detailed description of the volunteer programs. Resource Stewardship is described starting on page 24.

Sweet Fennel (Foeniculum Vulgare), a perennial herb that grows 4 to 10 feet tall. Its feathery leaves smell like licorice when crushed. It is commonly found along roadsides, trails, and in disturbed areas.

Arundo (Arundo Donax), sometimes called Giant Reed, this is a fast growing, bamboo-like, perennial grass that can reach 25 feet or more in height. It is usually found in or near stream beds.

Palm Trees, especially Mexican Fan Palms (Washingtonia Robusta), are common in Southern California, but are not native to the area. Mexican Fan Palms tend to grow in stream beds and in areas where water is near the surface, and they can be quite invasive.

Members of the COSCA Trail Watch, Trail Patrol and Adopt-A-Trail programs are encouraged to learn how to identify these invasive plants, and to note the locations of any observed plants on the reports they file.