Agency personnel are tasked with monitoring thousands of acres each field season. Due to constraints on time and finances, using efficient and informative monitoring techniques is paramount. In an effort to streamline data collection efforts, the authors sought to determine if a simple addition to the Daubenmire vegetative cover technique could be used to adequately monitor forb density for the Bureau of Land Management Sage-Grouse Habitat Assessment Framework. The study area was located in eastern Sublette County, WY, USA. The landscape is characterized by sagebrush steppe and associated ecosystem components. In order to minimize the influence of differing soil and precipitation regimes on study results, all sampling was restricted to a 230 acre area represented by a single ecological site. Within that area, ten sites were randomly selected (n=10). At each site, one 150' line was established. One team of two observers recorded the total forbs by species in each of 30, 20x50cm Daubenmire frames. Concurrently, another team of two observers recorded total forbs by species using the currently applied belt method (50' x 1m). Diversity and evenness estimates were calculated for each method using the Shannon-Weiner diversity index. Because observations were dependent, a paired-t test was used to determine if there were differences in forb density and diversity index values between sampling methods. Differences were considered significant when p<0.05. The modified Daubenmire method yielded higher forb density (32/m2) and diversity estimates (0.73) compared to the belt method (9/m2, 0.64). Differences for both comparisons were statistically significant. Based on these results, it is recommended that the BLM adopt the modified Daubenmire method as a way to seamlessly incorporate a required sage grouse habitat metric into range monitoring protocol.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.