COmpared Managed Prairie Systems (COMPS)
The COmparing Managed Prairie Systems (COMPS) experiment is a field experiment that began in 2014 and has since been completed.
The overarching research objective of this experiment was to determine how two factors, the timing of disturbance and plant functional group identity, interact to affect biomass production, plant community composition, and exotic species invasion in managed tallgrass prairie systems. The specific type of disturbance examined in this experiment was annual mowing in spring, summer, or fall with subsequent biomass removal. Prairie functional groups are categories of prairie plants based on phenology and growth form. Prairie functional groups examined in this study include warm-season grasses, cool-season grasses, early-flowering forbs, and late-flowering forbs.
Three main hypotheses were tested with this experiment:
1. Annual mowing during the period of active plant growth (spring and summer) will reduce aboveground and root biomass production compared to fall mowing with the greatest reductions in biomass production occurring in treatments with low functional group diversity.
2. Mowing will reduce the diversity (abundance and richness) of functional groups whose period of maximum growth coincides with the time of the mowing.
3. Invasive species will be more abundant in treatments that lack functionally-equivalent native species and in treatments where the timing of disturbance differs from the period of maximum growth of the invasive species.