Longleaf Pine Cone Production and the Influence of Super-Producing Trees

Abstract:Longleaf pine is a keystone species of the southeastern US that is undergoing restoration due to centuries of deforestation, fire suppression, and land-use changes. One important feature of longleaf pine is its episodic nature of cone production that is required for successful regeneration. To learn more about individual-tree dynamics of longleaf pine cone production, this study investigates the concept of “super producers” — a small number of individuals that produce a disproportionally large volume of annual seed crop compared to standard producers. I examined a 29-year cone-production dataset provided by the U.S. Forest Service that contained 234 longleaf pine trees from 18 sites throughout the Southeast. I found super-producing individuals at each site and these trees comprised 16.4 percent of all trees that were able to produce 31.6 percent of all cones in the dataset. Super producers were largely indistinguishable from standard producers based on trunk diameter, yet they were able to produce large cone crops when standard producers could not. The results of this study reveal a new understanding of the substantial variability of cone production at the individual-tree level that should be considered when managing regeneration efforts.