Location: Great Basin Rangelands Research
Project Number: 2060-13610-002-22-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 1, 2018
End Date: Jul 31, 2023
The ARS scientist will work with the Las Vegas district of the Bureau of Land Management (BLM) to investigate the effects of invasive species and proposed rehabilitation treatments on native plant species and desert tortoise habitat. In areas of desert tortoise critical habitat units in the Gold Butte National Monument, over 50 percent of the vegetative cover consists of red brome or Mediterranean grasses. Near Jean, Nevada, Mediterranean grass and Russian thistle appear to stabilize sand dunes and colonize habitat where white-margined penstemon lives. We will answer the following questions: 1. How does competition from non-native annual grasses affect native annual plant density and diversity? 2. How does competition from non-native annual forbs affect native annual plant density and diversity? 3. Do non-native annual plants create dune stabilization of sandy habitats, and how does this affect sensitive sand-dependent species? 4. How do repeated or variable herbicide treatments affect non-native and native annuals over time?
Projects may take place in various areas, including the Hidden Valley allotment, the Jean Special Recreation Managment Area (SRMA), and within the Gold Butte National Monument. Study areas would be in areas invaded by either Russian thistle (Salsola tragus), Mediterranean grass (Schismus barbatus), and/or red brome (Bromus rubens). The BLM will apply herbicide treatments to remove non-native invasive species, re-vegetate selected areas with galleta grass and other native perennial bunch grasses, and thus improve habitat conditions for sensitive species. Both herbicide and hand-pulling of non-native species would be used to compare and contrast these methods on surrounding plant communities, especially native annual species. Herbicide treatments would be used in areas that have been invaded by non-native species using imazapic-containing herbicide to reduce brome grasses, and glyphosate-containing herbicide.