The U.S. sagebrush steppe is a heavily degraded ecosystem that faces growing threats from increasingly frequent wildfires, juniper expansion and the spread of invasive species. Land managers use prescribed fire, herbicides, tree removal and shrub thinning to reduce these threats, as well as native plant seeding to restore biodiversity. However, these treatments disturb vegetation and soils and may create favorable conditions for invasive species. Cheatgrass is one of the most problematic invasive species in the western United States because it readily colonizes disturbed areas, outcompetes native herbaceous vegetation and alters fire regimes. It is already widespread across U.S. drylands, and even where its current abundance is low, environmental changes increase the risk of rapid future expansion.

Dryland vegetation worldwide is naturally dynamic, responding strongly to interannual environmental variability. Cheatgrass is no exception: Natalia’s recent research has shown that cheatgrass exhibits natural wave-like dynamics, with periods of rapid increase followed by decline, although the timing and magnitude of these waves vary among locations. She demonstrated that management treatments can amplify cheatgrass increases and that their long-term effects depend partly on how much cheatgrass was present before treatment. These results suggest that if treatments are implemented during a period of increasing cheatgrass abundance, when management may seem most urgent, they can inadvertently intensify future cheatgrass outbreaks. In contrast, actions that coincide with periods of natural cheatgrass decline could reduce the long-term risk of invasion. Restoration seeding may also be more successful when it coincides with a natural decline in cheatgrass, when native plants face less competition. By understanding these dynamics, managers may be able to work with natural vegetation dynamics rather than against them.

Natalia’s NW CASC project will investigate how climate fluctuations drive natural cheatgrass dynamics, focusing on sagebrush steppe ecosystems in Oregon and Washington. Natalia will use 20 years of field observations from the SageSTEP research network, including vegetation data from treated and control plots and detailed climate records from the study sites. She will also test whether satellite-based vegetation maps can provide useful information in places where long-term field observations are limited. Finally, she will develop a forecasting model to predict cheatgrass dynamics using both ground-based and remote sensing data and evaluate its results with independent datasets from the Bureau of Land Management. Natalia will work with partners from the Bureau of Land Management, the SageSTEP network and the U.S. Geological Survey to ensure that the research addresses management needs and that its products are easy to use. Planned products include an illustrated guide explaining cheatgrass dynamics and their implications for management timing, along with openly available forecasting tools and documentation.

Natalia aims to help managers identify when and where cheatgrass is declining, which may offer safer opportunities for land management and improve restoration seeding outcomes. The forecasting model will also identify periods when cheatgrass is increasing or near a peak, when treatments may carry greater risks and additional monitoring may be needed. The results could also support wildfire management by identifying time periods and locations with high levels of dry cheatgrass fuel and a greater risk of vegetation conversion after fire. Together, these products could help managers prioritize restoration and fire-management resources under changing climate conditions.