Evaluation of methods for restoration of tallgrass prairie in the Blackland Prairie region of North Central Texas

Abstract

The goal of this investigation was to initiate the restoration process of a facsimile prairie. Specific objectives were to evaluate the effects of time, topography/soil, seeding rate, mulch treatments and soil compaction on-the establishment phase of the restoration in a split-split-split plot experimental design. Three 24mx3Om replicate plots were established on summit, backslope and footslope positions. Each plot was subdivided into four treatment subplots which were planted with locally collected seed at rates of .3, .6, and .9 kg/ha pure live seed (PLS) (based on Sorghastrum avenaceum PLS). The fourth subplot was a control. One-half of each subplot was mulched with mechanically shredded seed hay. Subplots were further split into areas of soil compaction created by the wheel traffic of planting equipment. Across time, native perennial grass densities decreased and cover increased, while native annual forb density increased as canopy dominance decreased. Native perennial grass establishment was best within the summit and poorest within the footslope positions. Higher levels of soil compaction were deleterious to establishment of native perennial species, especially within the first growing season. Sorghastrum avneaceum plants successfully established under mulch-only applications, while other native perennial grasses had greater cover on mulched than on unmulched plots. Annual forb densities were less on mulched plots. Further, interactions with topographic positions and soil compaction often modified or nullified other treatment effects. For example, S. avenaceum densities for mulch treatments on compacted soils were not different than unmulched plots, regardless of compaction.