Canopy tree density and species influence tree regeneration patterns and woody species diversity in a longleaf pine forest

Longleaf pine once dominated much of the forested area of the Coastal Plain of the southeastern United States and is a focal forest type for restoration efforts. In these forests, two species dominate the canopy which may influence tree regeneration. Ultimately, the outcomes of habitat filtering, competition, and disturbance manifest in spatial patterns of tree regeneration, including in longleaf pine ecosystems. Understanding regeneration and establishment patterns can aid in restoration efforts. We ask how the dominant species in an established longleaf pine forest are spatially arranged to provide insight into the mechanisms that may be driving tree establishment in longleaf pine forests.

We found that longleaf pine saplings were more likely to be found near the other dominant tree species in this forest, turkey oak trees, than in gaps or near to longleaf pine trees. Similarly, turkey oak saplings clustered around turkey oak trees but were dispersed in relation to longleaf pine trees. These findings point towards the interplay between canopy tree composition, leaf litter, and fire behavior as driving mechanisms in the successful establishment of both pines and oaks in this forest.