Enhancing rangeland recovery by forecasting seed establishment

Background: In the western US, private, tribal, local, state and federal land managers are coping with millions of acres of rangelands that have been degraded by wildfire and invasive species. Effective ecological restoration practices are needed to help these rangelands recover and continue to provide benefits including grazing, recreation and energy development.  Direct seeding is frequently used to promote recovery of plant communities, but plant regeneration from seed remains a major bottleneck because the prevailing dry conditions in western rangelands often causes seeded plants to perish before they can become established.  Land managers could avoid this fate if they could focus their restoration resources in places and times where conditions will support plant establishment. This project is working to fill that information gap by synthesizing information about plant establishment and building a tool to deliver forecasts of restoration success, helping to maximize the chances that restoration efforts will be successful.

Objectives:

1. Survey and synthesize existing research about the environmental variables that control germination, emergence, survival, and growth for species that are used in restoration in western US drylands.

2. Develop models for plant establishment that leverage the literature synthesis in objective 1. These models will predict establishment as a function of the environment.

3. Translate models developed in objective 2 into operational forecasts that use medium-range weather forecasts to predict the outcome of restoration seedings.

Approach: Temperature and moisture conditions are notoriously variable in dryland regions, yet those conditions exert important influence over the outcomes of restoration seedings by controling seed germination and eventual plant establishment.  To understand these controls, we are compiling and analyzing a dataset of locations the Great Basin and Colorado Plateau with information about seeding treatments and outcomes.  We are applying a water balance model to estimate the conditions during the critical germination and establishment periods after seeding and building quantitative mathematical models that estimate the probability of plant germination or establishment if seeded.  

We are working to integrate this information into an online decision support tool to deliver forecasts of drought conditions and potential germination or establishment of seeded plant species over the next year (see Siegmund et al 2025).  An initial version of these forecasts is available in the "Drought Forecaster" tab in the Land Treatment Exploration Tool.  In this project we are expanding information in the forecaster to include additional species and life stages, and to include gridded forecasts across the western U.S., rather than the point forecasts currently available.  More information about the logic behind the drought forecaster is available here. 

Publications

• Siegmund, G.-F., D. R. Schlaepfer, C. Andrews, L. D. Bennion, J. Ferguson, M. I. Jeffries, P. Olwell, D. S. Pilliod, A. Simler-Williamson, A. E. Stears, R. Zweng, and J. B. Bradford. 2025. Supporting dryland restoration success with applied ecological forecasting of seeding outcomes. Restoration Ecology n/a:e70179. https://doi.org/10.1111/rec.70179.

Data releases

• Simulated daily soil moisture and temperature 1980-2023 to characterize environmental conditions for plant establishment.  U.S. Geological Survey Data Release. in prep

• Vegetation cover for eight perennial grasses from surveys conducted in the northern Great Basin and Snake River Plain for the Chronosequence and SageSuccess projects (2010-2014). U.S. Geological Survey Data Release. in prep

Presentations

• G-F Siegmund, A Stears. Understanding and forecasting environmental controls of plant establishment in dryland ecosystems to enhance restoration success. March 2025. USGS Sagebrush and Fire Research Series. Virtual.

• G-F Siegmund, D Schlaepfer, LD Bennion, A Stears, MI Jeffries, AB Simler-Williamson, D Pilliod, JB Bradford. Weather and ecohydrological influences on the outcomes of post-fire restoration seeding. February 2025. Society for Range Management. Spokane, WA.

• G-F Siegmund, D Schlaepfer, LD Bennion, A Stears, MI Jeffries, AB Simler-Williamson, D Pilliod, JB Bradford. Perennial plant recruitment dynamics inferred from post-fire restoration seeding. August 2024. Ecological Society of America. Long Beach, CA.

• G-F Siegmund, D Schlaepfer, MI Jeffries, LD Bennion, AB Simler-Williamson, D Pilliod, JB Bradford. Synthesizing knowlege about the environmental drivers of plant regeneration to support restoration seeding. February 2023. National Native Seed Conference. virtual.

• G-F Siegmund, D Schlaepfer, MI Jeffries, LD Bennion, AB Simler-Williamson, D Pilliod, JB Bradford. Synthesizing knowlege about the environmental drivers of plant regeneration to support restoration seeding. January 2023. Society for Range Management. Reno, NV.

• G-F Siegmund, D Schlaepfer, D Pilliod, AB Simler-Williamson, M Jeffries, JB Bradford. Environmental controls on plant regeneration in drylands: Synthesizing data and models to support restoration seeding. August 2023. Ecological Society of America. Portland, OR.