Graduate Research Assistant, South Dakota State University

Testing the Effect of Provenance on Native Seed Germination to Improve Seed-Based Restoration of Prairies

Grasslands are one the most endangered ecosystems on the planet and provide essential ecosystem services locally, regionally, and globally. Losses of grasslands can be mitigated through restoration. Seed-based restoration is a widespread option due to its practicality and cost-effectiveness. Planting seeds from non-local sources and may not be adapted for their destination climate can have consequences for germination and restoration success. Using data-informed decision-making when selecting where seed is sourced from is important in restoring grasslands so that germination can occur at the appropriate time and rate. Therefore, we examined the effect of seed source location on seed germination under different temperature regimes. We selected 13 native prairie species each with 3 commercially available county-specific seed source locations. To mimic spring temperatures, the germination chambers were set to 12-hour cycles of the average high and low air temperature for May 15th for Northern Minnesota, central South Dakota, and central Nebraska to encompass variation in temperature from a latitudinal gradient in grasslands of the northern Great Plains of the United States. For each seed source, five replicates of twenty-five seeds each were placed in plastic bags on moist blotter paper. Seeds from each source were placed in germination chambers and germination was recorded three times a week for 6 weeks. Final germination was examined using a relative interaction index (RII) = (Treatment – Control) / (Control + treatment). Control was considered the intermediate temperature and the treatments were the cooler and warmer temperatures. We found significant interactions between source and temperature in final germination percent for 7 of the 13 species tested. Results were species-specific. This shows that more than half of the species tested exhibit some local adaptation for germination characteristics. This study has implications for helping land managers make informed restoration decisions about sourcing seed.