Arundo and Tamarisk Control
The Salinas River watershed has the second-largest infestation of non-native Arundo donax (arundo) in California (apx. 1,500 acres). Arundo is a bamboo-like plant that forms dense stands and can grow over 30 ft tall. It crowds out native vegetation, degrades wildlife habitat, consumes large amounts of water, increases the risk of flooding to adjacent farm fields and cities, and poses a fire hazard.
The RCD of Monterey County is working with landowners, farmers, the Monterey County Agricultural Commissioner’s office, and other stakeholders to implement the Salinas River Invasive Non-Native Plant Control and Restoration Program, with a goal of eradicating arundo and along 90 infested river miles in 20 years.
In the first phase of the program, supported by the Monterey County Agricultural Commissioner and the California Department of Food and Agriculture, arundo was sprayed between King City and the Monterey/San Luis Obispo county line in 2008 and 2009.
The next phase of the program began in 2014 with funding from the California Wildlife Conservation Board and the Monterey County Agricultural Commissioner. Beginning near Greenfield and working downstream, the RCD is mowing and spraying arundo, as well as tamarisk (Tamarix parviflora), tree tobacco (Nicotiana glauca) and other non-native woody vegetation.
Treatment of large stands begins with mowing in the fall, which reduces standing biomass and causes a flush of regrowth from the underground rhizomes in the spring. Arundo resprouts are then sprayed with aquatic-approved herbicides the following summer, and in each subsequent year until no sprouts remain. Smaller, scattered stands are treated with herbicide without prior biomass reduction.
The RCD’s roles in administering the program include fundraising, securing required permits, recruiting landowners into the program, overseeing the implementation of weed control activities on private lands, providing biological monitoring of treated areas, ensuring regulatory compliance, and coordinating financial and technical assistance for private landowners interested in performing their own control efforts.
As a result of the program, over 450 acres of arundo are under control. The RCD continues to seek funding and landowner cooperation to advance the program downstream.
If you are a landowner or grower interested in arundo control on your Salinas River property, contact Emily Zefferman.
Learn more about our Salinas River Invasive Plant Control and Restoration Program by watching this short video, WITHIN REACH: Releasing Arundo's Leafy Grip on the Salinas.