Patterns and Drivers of Wiregrass Gap Longleaf Pine (Pinus palustris Mill.) Woodland Succession as Part of Restoration Efforts

Longleaf Pine (Pinus palustris) communities are widespread throughout the Southeastern United States with a dominant understory vegetation of wiregrass (Aristida spp.) in most of its range. A small area in central South Carolina that is naturally free of wiregrass is called the “Wiregrass Gap”. Here, the understory vegetation is dominated by bluestems grasses (Andropogon spp. and Schizachyrium spp.) which drive the disturbance regime of frequent low-intensity fire. The successful establishment of these grasses is key for longleaf pine woodland restoration efforts in this region, but few resources detail the ecological drivers at play that enable successful restoration in these longleaf pine woodlands. I investigated these drivers of succession through the lens of slash manipulation treatments that resulted from a restoration harvest. Exposed duff and mineral soil had a favorable effect on the herbaceous response but also benefitted the regeneration of many loblolly pine seedlings. This complicates restoration efforts. An abundance of woody material was suspected as a suppressant of establishing vegetation. In addition, I investigated how early successional plants can contribute to the restoration process. By quickly establishing in soil devoid of arbuscular mycorrhizal fungi that are vital for plant growth, early successional plants can enhance the arbuscular mycorrhizal inoculum in the soil and successfully preconditioning it for the benefit of later successional plants as they colonize the site. The restoration of Wiregrass Gap longleaf pine communities is thus adaptable to different induced and ecological drivers that together can result in successful woodland restoration