THE LAND CONSERVANCY OF SAN LUIS OBISPO COUNTY

Restoration Project: Arundo donax

San Luis Obispo Creek watershed

Overview/History

Arundo donax, a native of the mediteranean region, is a scourge to streams all over California, including the San Luis Obispo area. The plant is often described as being like bamboo because the canes have nodes similar to bamboo. Because it has no natural predators here, the plant grows unabated and can overtake and replace the native vegetation that local fish and wildlife depend upon to live. Arundo grows very quickly, and in some studies, grew upwards of 6 inches a day. It is a voracious water consumer, which makes it a threat to some streams that have little water to support fish. It also contains volitale oils that make it a fire hazard. All around, this plant is bad news for local creeks.

The Problem

In the San Luis Obispo Creek Watershed Invasive Plant Management Plan (produced by the Land Conservancy in 2002), Arundo was designated as the top priority for weed management along the creeks.

Project Approach

Fighting Arundo isn't easy because it is a very persistant plant and it spreads easily from cane and root fragments. Therefore, all parts of the plant removed must be specially handled to prevent spread. Since Arundo spreads primarily downstream from broken canes or roots, the eradication effort has to target upstream plants first. Making sure we were systematic took a lot of mapping and planning, as well as getting permission from private landowners to remove the plant on their property. Once treated, the sites must all be monitored to make sure the plant is dead and to re-treat if necessary. We are fotunate that the landowners along the creek understand the problems this plant can cause and worked cooperatively with us to get the work done.

Results

As of summer 2009, our crews have treated arundo plants in about 3/4 of the affected areas. With continuing grant support, we believe we can have the plants remioved throughout our local streams within a year. This would make San Luis Obispo Creek and its watershed the first california watershed to have Arundo completely removed. Even when we are complete, we will need to keep an eye out to make sure we don't get a re-infestation.

Project Partners

With grant support from the Department of Fish and game and the Avila beach Trustee Council, the Land Conservancy has begun an effort to remove this plant from San Luis Obispo Creek and its tributaries.