Timing of burning and mowing management of a bluestem prairie in eastern Nebraska.

This study evaluates the effects of time of mowing on species composition and inflorescence phenology in a bluestem prairie and contrast mowing and burning treatments. Treatment areas in a native prairie, with a history of summer mowing, were burned and mowed in April and evaluated in June and August of the same year. While reflecting only a single year’s treatment, the study indicated that summer mowing favors cool season grasses, such as porcupinegrass (Stipa spartea), and selects against warm season grasses such as big bluestem (Andropogon gerardii). Canopy coverage, biomass, and flowering stem numbers and height of porcupinegrass was consistently greater in summer mow plots than on spring burn and spring mow plots. In comparison, big bluestem was favored by spring burning and spring mowing. The effect of spring and summer mowing treatments on overall species composition is suggested in slight but consistent responses of cool and warm season forbs in grass species; spring mowing favors warm season species and summer mowing favors cool season species. Comparisons between spring mowing and spring burning treatments suggest first, that time of mowing is equally as important as time of burning, and second, that while not duplicating burning results, mowing in the spring seems to be a next-best alternative for maintaining bluestem prairie species diversity. Consideration of these differences with respect to time and burning and mowing is important in planning for the maintenance of native bluestem prairie ecosystems