Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: February 2, 2003
Publication Date: N/A
Technical Abstract: Water availability is a primary determinant of successful plant establishment on western rangelands. Two major factors that determine water availability are seasonal and annual patterns of precipitation and the presence of competitive annual weeds. In this study, we calibrated the SHAW microclimatic model and simulated hourly temperature and moisture at seeding depth for a 38-year period in southwestern Idaho. A hydrothermal-germination model for bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) Löve], big squirreltail [Elymus multisetus (J.G. Smith) M.E. Jones] and cheatgrass (Bromus tectorum L.) was used to assess potential germination response for every day of the 38-year microclimatic simulation. Probabilistic-germination indices were developed to compare relative germination response as a function of seedbed microclimate. Model simulations of this type can be used to evaluate alternative management treatments and plant materials; and to incorporate medium and long-term weather forecasts into real-time management planning. In order to take full advantage of these tools, however, it is necessary to separate short-term soil stabilization, and long-term biodiversity and restoration objectives.