1a. Objectives (from AD-416)
The overall ovjective is to develop and implement a comprehensive, regional Ecologically-based Invasive Plant Management (EBIPM) program to restore ecosystems threatened and dominated by cheatgrass/medusahead in Smoke Creek watershed and the Great Basin.
1b. Approach (from AD-416)
University of California, Davis (UC-Davis) and USDA, Agricultural Research Service (ARS) scientists will cooperate on a project to demonstrate the effectiveness of Plateau on the large scale control of downy brome and medusahead, and to determine its utility in sage grouse habitat restoration of desirable native species without the need for expensive re-seeding efforts. Secondly, to consider alternative methods of control with and without re-seeding efforts, and to determine the best seeding method when active restoration practices are necessary (refer to project proposal for more detailed information). Documents SCA with UC-Davis.
3. Progress Report
The goal of this project is to develop and implement a regional EBIPM program to restore ecosystems threatened and dominated by annual grasses in the Smoke Creek watershed which contributes directly to Subobjectives 1.1 and 1.3 of the Area-wide pest management project for annual grasses in the Great Basin. Large and small plot sites were identified and all herbicide treatments were applied during the past year. In June, 2009 evaluations of both plots were conducted. In each of the treated and untreated sites, 20 quadrat evaluations (20 cm x 50 cm) were conducted in the sagebrush and grassland areas within the large plots. At each site, there were 80 total quadrats evaluated and collected. In addition, 10 line transects were made in the sagebrush areas of both the treated and untreated areas to determine the cover of shrubs. All quadrat samples were evaluated at UC Davis for biomass for each invasive grass, other annual grasses, perennial grasses, and broadleaf species. In addition, stem and inflorescence counts for downy brome and medusahead, and average number of seeds and inflorescences were also evaluated per quadrat. Downy brome and medusahead seeds were germinated to determine percent viable seed for per unit area in treated and untreated areas. Biomass will be determined for each category, which includes medusahead, downy brome, and other species. Our results indicated that the treated area had very low levels of medusahead and downy brome compared to untreated areas. In addition, the sagebrush was unaffected by the Plateau (imazapic) treatment. Based on results from our small plot experiments, we treated a second year with Matrix (rimsulfuron). Two small plot sites (5 acres each) were located just west of Nevada in Lassen County, California. Plots were treated in fall with Plateau at 6 oz product/acre, Matrix at 4 oz product/acre, sulfometuron + chlorsulfuron (Landmark XP) at 1.0 oz product/acre. An addition treatment with glyphosate (Roundup Original 4L) at 16 oz/acre was made in April, 2009. There was also an untreated control. Five quadrats were evaluated per plot for a total of 20 per treatment. Samples are currently being evaluated for the same parameters as large plots. Results of our findings indicate that Matrix is a very effective tool for control of both downy brome and medusahead, and provides safety to both desirable perennial grasses and sagebrush. Seeding treatments were made in fall of 2009. In another experiment, we tested the effect of low rates of glyphosate at three treatment timings on medusahead control. Analysis is in progress. All aspects of the project are within the timetable established in the agreement. ADODR monitoring progress through meetings and telephone conference calls and multiple site visits.