Problem

Arundo donax is a non-native bamboolike grass that invades riparian areas and displaces native vegetation in the Russian River Watershed. Russian River Team Arundo leads removal and native vegetation efforts in riparian corridors to enhance biodiversity in habitat adjacent to natural and agricultural lands.

The Russian River Watershed has an estimated 4850 acres of riparian areas infested with Arundo donax (Table I.). This non-native weed absorbs soil moisture, shades out native plants, and presents a significant fire hazard.

Table I. Russian River Watershed reach, total riparian area infested with Arundo and percent Russian River Watershed infestation (September 2008).

Reach	Infested Riparian Area acres	Watershed Infestation %
Mendocino County	830	17
Alexander Valley	2206	46
Dry Creek Valley	219	5
Healdsburg to Green Valley	1456	29
Lower reach	139	3
All Reaches	4850	100

Watershed Assessment

Russian River Arundo infestations are documented using multiple technologies. An initial survey was performed with video during winter dormancy when infestations are most easily identified. Infestations visible in the video were then located on the aerial photographs. Infestations were digitized into Geographic Information Systems (GIS) maps. Maps provide visual reference in the field and office for job progress and estimating.

Video documentation for reference

Riparian infestation mapping

Landowner Outreach

The Russian River Watershed is 98% privately owned. Because of this eradication of Arundo donax in the watershed will only be successful with the investment and commitment of private landowners, environmental groups, local, state, and federal agencies, and the public.

A strong emphasis has been placed on community outreach including workshops, literature, and landowner consultations. The RCDs work collaboratively with landowners to remove Arundo and restore riparian habitat. Each removal site includes a detailed, customized plan developed with landowner oversight and approval. To date 115 landowners have participated in the removal program.

Tailgate meetings as effective outreach

Infestations treated near agricultural lands

Hand Removal and Riparian Planting

Hand removal with riparian plantings offers a comprehensive strategy for restoration. Hand removal is ideal for localized infestations and on sites with prohibitive access. In order to ensure quality restoration, Arundo stands are removed by hand and riparian areas are planted, regrowth is controlled by herbicide or by tarps.

Treat using loppers and weed eaters Paint herbicide for local control	Enhance riparian areas with native plants Tarp for a non-chemical approach

Mechanical Removal

"Russian River weeds mowed down in a flash" Press Democrat 6/13/07

Due to the environmental impact of mechanical removal, Russian River Team Arundo drafted a CEQA Mitigated Negative Declaration. Mechanical removal requires precise timing and coordination. To ensure quality treatment, bird surveys are conducted, Arundo stands are mowed, native vegetation is avoided, and regrowth is sprayed.

Treat using tractor mounted flail mower Ensure native vegetation is intact	Survey birds during nesting season Spray regrowth during dry season

Progress

Major efforts in the program are being led by mechanical removal efforts in the upper and central Alexander Valley. Hand removal in the tributaries and mainstem of Mendocino County continues as does removal in the Dry Creek Valley.

Lower Alexander Valley, Healdsburg, and lower reaches will become a higher priority after further progress upstream (Table II).

Table II. Russian River Watershed reach, total riparian area treated / under landowner agreement and percent of Russian River reach treated / under landowner agreement (September 2008).

Reach	Infested Acres	Infested acres under treatment or under landowner agreement	Reach Treatment %
Mendocino County	830	590	71
Alexander Valley	2206	1221	55
Dry Creek Valley	219	127	58
Healdsburg to Green Valley	1456	618	42
Lower reach	139	7	5

Mitigated Negative Declaration

The Sotoyome RCD, as the lead California Environmental Quality Act (CEQA) agency, has determined that the Giant Reed (Arundo donax) removal project in the Russian River watershed qualifies for a Mitigated Negative Declaration pursuant to CEQA. Notice of Determination is on file with the California State Clearinghouse and can be viewed at www.ceqanet.ca.gov - or is available for public review at Sotoyome RCD's office located at 2150 West College Ave, Santa Rosa, CA 95401.

• Mitigated Negative Declaration - October 2004
• Addendum #1 - January 2007
• Addendum #2 - April 2009

Map of Giant Reed in the Russian River watershed

Area maps:

• Austin Creek
• Coyote Valley
• Forsythe
• Geyserville
• Guerneville
• Laguna de Santa Rosa
• Santa Rosa - Mark West
• Sulphur Creek
• Ukiah
• Warm Springs

Program Funding

For more information about the Sotoyome RCD's Arundo donax Removal Program,
please call us at (707) 569-1448 or e-mail info@sotoyomercd.org.