Since January 2011, the EROS team studying cheatgrass in the Great Basin has made significant strides developing datasets that identify cheatgrass extents and abundances and cheatgrass dieoff in and around the Winnemucca, Nevada area. Additionally, the team, in partnership with the BLM, received money from the USGS’ Northwest Climate Science Center to expand our cheatgrass dieoff study area to most of the northern Great Basin. In the Winnemucca area, we developed a regression-tree model, trained on Peterson’s cheatgrass maps, that generated a time series (2000 – 2010) of cheatgrass extents and abundances and then analyzed the relationships between this cheatgrass time series and spatially explicit site-specific variables like elevation, slope, aspect, and a dynamic variable, annual precipitation. We used the cheatgrass time-series dataset to build a time series (2000 – 2010) of weather-based ecosystem performance anomaly models that identified cheatgrass dieoff areas. In the expanded study area covering the northern Great Basin, we are currently developing the time series of cheatgrass extents and abundances. Future plans include developing a time series of weather-based ecosystem performance anomalies to identify areas of cheatgrass dieoff across most of the northern Great Basin. Our final objective is develop cheatgrass dieoff probability models that will use regression-tree techniques along with future climate data to predict areas of future cheatgrass extents and abundances and potential areas of future cheatgrass dieoff.
