CIR to Remove Tamarisk in the San Rafael Wilderness

The National Fish and Wildlife Foundation (NFWF), in partnership with the US Forest Service, has awarded CIR a large grant to eradicate nonnative tamarisk trees that are invading the Sisquoc River, Manzana Creek, and their associated tributaries. 

In the wake of the Zaca fire, invasive plants have established a foothold in this remote area of wilderness - most concerning among them tamarisk (also known as salt cedar). Tamarisk, a deciduous shrub or small tree native to Eurasia, thrives in streambeds with often little to no water by use of its deep and extensive root system that it uses to draw up groundwater. Not only does their thick root system crowd out the roots of other native plants, but it consumes huge amounts of water turning streams to bone dry washes. Tamarisk readily regenerates from remnant roots after the rest of the tree is scoured away from a flash flood. A single tree can produce as many as 500,000 seeds in a single growing season. Suffice to say, tamarisk poses a very serious threat to any ecosystems it invades.

The remote backcountry streams of the Los Padres National Forest give refuge to a large number of rare and endemic species. Among these are the arroyo toad, California red-legged frog, and steelhead trout, all of which are federally listed as threatened or endangered. By eradicating tamarisk trees, our project will provide an opportunity for native plants to reestablish themselves, thereby restoring this critically important habitat.

We are honored to be awarded this grant that allows us to undertake this project and we are humbled at the scope of what will be necessary to complete this project. In total, we will remove tamarisk within 61 miles of backcountry streams. Because there is no motorized access to most of the project area, all personnel and supplies will be packed in on foot and a mule pack train. Tamarisk trees will be removed in a way that does not impact the sensitive riparian habitat that they have invaded.

   
Sisquoc River in the San Rafael Wilderness
photo by Chris M. Morris