Project period: 4 22 24-4 21 25PROJECT title: climate-smart vegetation treatments: leveraging 15 years of sagestep climate, soil moisture, and vegetation data to inform management of resilient…

The U.S. Geological Survey (USGS) has awarded a $211,399 Cooperative Agreement to Oregon State University (OSU) under the USGS Research and Data Collection program (CFDA 15.808). The project, titled "Climate-Smart Vegetation Treatments: Leveraging 15 Years of SageSTEP Climate, Soil Moisture, and Vegetation Data to Inform Management of Resilient Ecosystems", aims to analyze 15 years of SageSTEP network data to determine the efficacy of woody plant thinning treatments in mitigating drought impacts and promoting resilient sagebrush and woodland ecosystems in the Great Basin. Key deliverables include 1-2 peer-reviewed publications, a practical guide for land managers, webinars, and publicly available datasets. The project will leverage OSU's expertise in climate, soil, and vegetation dynamics to provide forward-looking guidance on using vegetation treatments to improve drought resilience in the sagebrush steppe biome.

Project period: 4 22 24-4 21 25PROJECT title: climate-smart vegetation treatments: leveraging 15 years of sagestep climate, soil moisture, and vegetation data to inform management of resilient ecosystemsland managers need to promote resilient sagebrush and woodland ecosystems in the face of joint threats of wildfire and heat drought stress. Hotter, prolonged droughts could impact both pinyon and juniper mortality and recruitment, which may slow or reverse woody expansion, but also contribute to fire risks to human communities and threaten trees in long-established woodlands and forests. Sagebrush may also be increasingly vulnerable to DIE-off under extreme drought, such that managers will need to consider adaptive actions to support shrubland drought resilience. Vegetation treatments such as woody plant thinning, and prescribed fire are potential tools for manipulating ecosystem resilience to climate threats. Woody plant thinning treatments have the potential to improve ecosystem drought resilience by reducing evaporative demand and increasing soil moisture available to remaining plants. Hypothesize that vegetation treatments in sagebrush and woodlands interact with drought and other climate variables in ways that influence plant regeneration, expansion, and persistence over time. Propose to leverage 15 years of observations from a broad-scale experiment (sagestep) replicated across the great basin to characterize climate influence on control and treated sites and ascertain how treatment-climate interactions have mediated soil moisture, tree and shrub recruitment and mortality dynamics, and understory plant community dynamics across diverse environmental settings. Will provide information on how these ecosystems and their microclimates are already changing across the biome, and forward-looking guidance on how vegetation treatments may mitigate drought impacts in the future. By leveraging this 15-year empirical time series for soil water balance modeling, will be able to project how treatments may influence soil moisture and evapotranspiration under future climate conditions. Furthermore, the geographic spread of sagestep sites across the great basin allows for comparative breadth across different environmental contexts that can inform judgments of where treatments are most likely to have desired outcomes or alternatively, where they may have unintended consequences for plant community change and drought resilience.objectives:1.analyze 15-year trends in climate and soil moisture across the sagestep network of meteorological stations. Relate treatment-microclimate interactions to tree and shrub recruitment and mortality dynamics.2.determine how effective woody plant thinning treatments are at mitigating drought threats by increasing soil moisture and promoting resilient ecosystems.proposed deliverables:1.1-2 peer-reviewed manuscripts describing methodology, results, and implications.2.a practical guide for land managers summarizing implications for land treatment decisions to improve drought resilience in sagebrush steppe throughout the great basin.3.webinars to managers and policymakers via USGS, USFS and or the great basin fire science exchange.4.dissemination of results on the USGS and sagestep websites.5.final datasets made publicly available through USGS sciencebase.