When it rains it pours: Impacts of deluge events on Bouteloua gracilis seeding
Category: Research Poster
Author(s): Carlie Clemmer, Sean Kirkpatrick
Presenter(s): Carlie Clemmer
Mentors(s): Madelyn Amick
Climate change is predicted to alter precipitation regimes, resulting in more frequent severe drought and deluge events. Despite this, we remain unsure about how drylands recover from drought and interact with deluges. Extreme drought events have been shown to decrease the abundance of dominant plant species, as observed in Colorado’s shortgrass steppe with the loss of Bouteloua gracilis. Seeding dominant plant species following drought may improve recovery, however, little data is available. Seeding efforts often use cultivars, such as B. gracilis’ Hachita and Lovington which are used for restoration but lack published data regarding the efficacy of their use for drought recovery. We examined the impact of a post-season deluges on the germination of these cultivars. We seeded our cultivars in April 2025, following a four-year experimental drought that diminished the B. gracilis population at the Central Plains Experimental Range. A post-season deluge event was applied to deluge plots in October 2025. Germination, survival, and established perennial cover were measured in deluge and ambient (control) plots. In previously droughted plots, deluge significantly increased the number of Lovington seedlings that germinated, and non-significantly increased that of Hachita (p < 0.05). Lovington was more successful, with more seeds germinating per plot, on average, than Hachita. Cover of established perennials was positively correlated with the number of seedlings that germinated. These findings suggest that deluge events may increase the efficacy of seeding after drought regardless of cultivar selection. However, we suggest that further investigation into the legacy of these deluge events is required.