Open canopy conditions in southeastern pine (Pinus spp.) forests were historically maintained by frequent fire and other disturbances, without which midstory hardwoods create closed canopy conditions limiting value of pine stands for many endemic, disturbance-adapted species. Intensively managed pine forests, which comprise 19% of forests in the southeastern U.S., can emulate historical open pine conditions, providing appropriate vegetation structure and composition for many endemic species. However, exact mechanisms for producing and maintaining open pine conditions and subsequent effects on biodiversity have not been examined across regions and stand ages. To better inform managers about options for providing open pine conditions in intensively managed pine stands, we used meta-analyses to examine biodiversity and open pine focal species responses to 5 stand establishment intensities and 4 mid-rotation practices (prescribed fire, selective herbicide, fire and herbicide combination, and thinning). We calculated 1742 biodiversity and 169 open pine focal species effect sizes from 42 publications of manipulative studies at 14 unique study sites in managed loblolly pine (P. taeda L.) forests in the Atlantic and Gulf Coastal Plains of the southeastern U.S. We quantified diversity and abundance responses by taxa and management practices for vegetation, birds, amphibians, reptiles, small mammals, and invertebrates. Diversity and abundance responses generally decreased as stand establishment intensity increased, but those reductions appeared to be short-term (<3 years). Birds and open pine focal species responded positively to chemical stand establishment relative to a mechanically-prepared control. Thinning elicited positive diversity and abundance responses from reptiles and small mammals. Effects of prescribed fire, selective herbicide, and their combination on biodiversity responses varied by taxa (e.g., following fire, vegetative and avian diversity increased but amphibian and invertebrate diversity decreased). Further research is warranted on under-represented taxa (e.g., herpetofauna and invertebrates) in literature and long-term effects of forest management on biodiversity. Understanding how silvicultural management practices produce and maintain open pine forest conditions and influence biodiversity responses is necessary to inform opportunities for open-pine wildlife communities in working forested landscapes
