PULLMAN, Wash. — Scientists and land managers in Washington and Oregon have received a five-year, $500,000 grant from The Nature Conservancy to field test a bacteria that may give land managers a new tool to suppress cheatgrass and restore degraded rangeland.
Cheatgrass is an invasive annual weed that infests an estimated 50 million acres of rangeland in West. Cheatgrass grows in the late fall and early spring, outcompeting native plants. It dries out in the summer providing a continuous layer of fuel for wildfires, and it has the potential to destroy more than 100 million acres of sagebrush country.
“The use of naturally occurring bacteria as a bioherbicide against an invasive species represents a new concept for rangeland management,” said Ann Kennedy, USDA-Agricultural Research Service Soil Scientist and adjunct professor of crop and soil sciences at Washington State University.
Kennedy identified the potential biological control agent during research on weed-suppressive bacteria. “It is capable of selectively inhibiting cheatgrass,” she said.
The microorganism — the bacterium Pseudomonas fluorescens strain D7 — is native to Washington soils and has been shown to inhibit germinating cheatgrass seeds in laboratory, greenhouse and field trials while not harming other species.
The grant will enable researchers and land managers to evaluate the effectiveness of the bacteria under a range of environmental conditions with understory restoration in areas that have sagebrush cover. The results of this study will be used to develop management strategies that will both prevent further rangeland degradation and serve as a tool in restoring infested land.
Partnering with The Nature Conservancy on the project are Tami L. Stubbs, associate in research, WSU crop and soil sciences department, Tony Svejcar, USDA-ARS rangeland scientist in Burns, Ore.; the Bureau of Land Management and the U.S. Forest Service. The Conservancy collaborators are Sonia Hall, arid lands ecologist, and Chuck Warner, Moses Coulee conservation area program director.
The Nature Conservancy is a leading conservation organization working around the world to protect ecologically important lands and waters for nature and people.