Plant community composition and structure monitoring for Badlands National Park: 2011-2015 summary report

Ashton, Isabel; Davis, Christopher

The Northern Great Plains Inventory & Monitoring Program and Fire Effects Program have been monitoring vegetation in Badlands National Park (BADL) for over 18 years. While methods have changed slightly, this report summarizes data from over 127 locations in BADL’s north unit from 1998-2015. We use these data to explore the status and trends in plant communities, the role of climate and disturbance in maintaining species richness, and the occurrence of rare plants. A summary of the current condition (2011-2015) and trends (based on 1988-2015) in plant communities at BADL is found in the table below. 1. What is the current status of plant community composition and structure of BADL grasslands (species richness, cover, and diversity) and how has this changed from 1998-2015? BADL plays a vital role in protecting and managing some of the largest remnants of native mixed-grass prairie in the region. Most sites within the park have a number of native grass and forb species that is well within the natural range of variability for northern mixed-grass prairie. We found no significant changes in native species richness or evenness from 1998-2015, but both metrics are threatened by the increasing cover of exotic species. Annual bromes, Kentucky bluegrass, and yellow sweet clover are the most abundant exotic plant species in BADL. Continued management efforts will be necessary to maintain native prairie within BADL. 2. How do trends in grassland condition relate to climate, fire history, and the presence of bison? The large variability in the climate of BADL has made it difficult to discern strong patterns linking temperature, precipitation, to plant community structure (e.g. exotic cover, diversity). However, we did find that the relative cover of exotic species declined in response to increasing average annual maximum temperatures. Continued monitoring and a longer time series of vegetation data and climate will allow us to determine if hotter conditions continue to favor native species. BADL has been using prescribed burning as a management tool since the 1980s. There was no difference in native diversity or exotic cover among plots that had burned recently and those that had not burned for over 10 or 25 years. However, plots that had not burned in many years had a higher cover of annual bromes than sites that burned more recently. Ongoing adaptive management programs and research will provide better guidance to park managers on whether prescribed burns should be used to reduce the cover of annual bromes. We found that native species richness was higher in plots within areas of the park utilized by bison. This pattern is consistent with a past studies on the role of disturbance in maintaining grassland diversity. 3. What, if any, rare plants were found in BADL long-term monitoring plots? We found only one rare plant in BADL. Barr’s milkvetch (Astragalus barrii) was observed in a single vegetation monitoring plot. Since the rare plants within BADL are found in such low abundance, we recommend a more targeted effort to monitor their populations.

Plant community composition and structure monitoring for Badlands National Park: 2011-2015 summary report

Series

See also

Collections