Using the past to inform future seed sourcing in the Colorado Plateau

Background/Question/Methods

Investigating how the native plant materials used in a restoration influence its short- and long-term outcomes can provide valuable data to inform future restoration efforts. For example, using historical data on restoration seed mixes and outcomes can help identify species and seed sources that have a demonstrated ability to establish and persist in different restoration settings. In order to make this possible, researchers need access to detailed data on restorations carried out over multiple sites and multiple years. Ideally, this information would include species and seed sources used, as well as monitoring data prior to and over the course of many years following implementation of the restoration. While it can be challenging to find robust datasets that meet these requirements, the Utah Watershed Restoration Initiative (WRI) has created an excellent database for Utah that fits these requirements and presents a unique opportunity to use past restoration efforts to inform future seed sourcing in the Colorado Plateau. Using a dataset of all seeded habitat restoration sites in the Colorado Plateau implemented and monitored by the WRI between 2003 and 2014, we evaluate the use of plant materials used in restoration seed mixes.  In addition, we use a spatial and temporal approach to evaluate when and where the use of different species, seed mixes, and seed sources impact the outcome of restoration efforts.

Results/Conclusions

The full dataset includes 51 native and introduced grass and forb species seeded at 126 habitat restoration sites in eastern Utah. Among seeded species, sources included 61 cultivars and 41 seed lots sourced from known locations (e.g., source-identified seed). We summarize use and performance data for 10 of the most commonly used native species in this dataset, assessing the environmental conditions at known seed source sites relative to the range of environmental conditions at restoration sites. We also use pre- and post-restoration monitoring data to identify sites and conditions under which each species and seed source is likely to have germinated and persisted over multiple years. By incorporating information on how plant materials currently available for use in restoration perform in the short- and long-term under restoration site conditions, study results will be useful to help inform seed sourcing decisions in the Colorado Plateau.