The Russian River watershed, once home to the largest steelhead population in the world, is increasingly being invaded by a nonnative weed that threatens the viability of numerous fish and wildlife species. The highly destructive giant reed (Arundo donax) is degrading native riparian habitat, which includes such species as alder, willow, and cottonwood.

Giant reed is a bamboo-like grass, native to Asia, which has been wide-spread in some Mediterranean countries for centuries. It was brought to California by early settlers from Spain, who used it to build animal shelters and other enclosures. It was also planted in the 1940s and '50s by people who believed that it was effective in controlling erosion. Landowners have since learned that willows are far more effective, for the reed has a shallow root system.

This very invasive reed grows up to thirty-five feet high, is highly flammable, uses large amounts of water, and rapidly takes over streamside vegetation. In some California stream systems, solid stands of giant reed have replaced diverse riparian forests within ten years, creating a monoculture that supports very few wildlife species. Arundo donax is an enormous problem in many coastal watersheds, particularly in southern California. It has created a monoculture on some reaches of the Santa Ana and Santa Margarita Rivers, is widespread on the Ventura River, and has begun to infest other rivers to the north, including the Gualala and the Sacramento.

Riparian habitat is critical to the long-term health of the salmonid fishery, providing shade over stream channels, as well as a long-term source of food and “large woody debris” to the aquatic environment. Considering that the Russian River is home to three federally listed salmonid species—steelhead trout, and Coho and Chinook salmon—the replacement of native riparian vegetation by the giant reed is a serious natural resource management issue.

Circuit Rider Productions, Inc., a nonprofit agency specializing in ecological restoration and watershed planning, began a giant reed removal program on the Russian River in 1999 with start-up funding from the Sonoma County Water Agency, the Sonoma County Community Foundation, and numerous landowners and community groups. In May 2000, the Coastal Conservancy enabled the program to expand considerably by approving $121,000 for the Giant Reed Extraction and Enhancement Program.

The reeds will be cut down by hand, with loppers and machetes. Landowners will follow up by tarping, removing new growth by hand, or careful application of low-impact herbicides approved for such use. The choice of method will be the landowner's. The Circuit Rider program will restore native riparian habitat, educate the public about giant reed, and involve volunteers in the fill removal and restoration program.

—Karen Gaffney

For more information about giant reed in the Russian River watershed, contact Circuit Rider Productions, Inc. at (707) 838-6641 or crp@sonic.net. For information about giant reed, see the Team Arundo del Norte website: ceres.ca.gov/tadn/.