Use of Resource Partitioning and Disturbance Regimes in the Design and Management of Restored Prairies

The natural processes responsible for the origin and maintenance of native grasslands must be understood in order to restore North American prairies effectively. Grasslands historically have predominated where the climate ranged from semiarid to mesic but with periodic droughts, and where fires repeatedly removed dead above­ ground biomass and retarded encroachment of woody invaders. As in most North American ecosystems, however, the particular assemblage of species naturally found at a site is frequently of recent origin and is not necessarily a stable combination. The establishment and persistence of many mature pra1r1e species may depend on specific soil moisture conditions that facilitate their localized competitive superiority. Both successional and climax prairie species may depend on some sort of general or local disturbances to free space for seedling establishment. Frequent disturbance in the form of fire, grazing or mowing is needed to remove standing dead plants and accumulated litter but this can cause varying effects on community composition. Established perennials are difficult to displace. Poor establishment from·seed and constant invasion by exotic C3 grasses, forbs and woody plants are the most common problems in prairie