More than just timber: silvicultural options and ecosystem services from managed southern pine stands
This article is part of a larger document. View the larger document here.Abstract
The dramatic decline of timber harvests on public lands in the western United States (U.S.) has helped intensify silviculture in the southern U.S. Today, intensive southern pine management usually involves establishment of plantations using site preparation, genetically improved seedlings, chemical fertilization and competition control, early stand density regulation, and increasingly shorter rotations. Little is known about the consequences of this intensification on the ecosystem services provided by pine-dominated forests. Using a synthesis of field studies, simulations, and literature reviews, we compared the impacts of different management options on key services such as diversity, forest productivity (including carbon sequestration), and erosion and other site-related qualities. This review suggests that naturally regenerated pine stands tend to be more structurally and compositionally diverse than plantations, especially as management intensity decreases. Currently, well-managed naturally regenerated pine stands yield only 50 to 90 percent of the wood fiber produced by plantations but in forms more conducive to long-term sequestration in structures. Carbon sequestration is largely a function of stand density, treatment timing, and what is counted as “stored carbon.” Plantation establishment also typically involves more soil disturbance, thereby increasing the potential for short-term sedimentation, soil compaction, and drainage issues and may provide accelerated problems with invasive species. Because of the greater tangible cash value of timber yield as an ecosystem service, natural regeneration will not replace pine plantation silviculture for landowners focused largely on commodity production. However, since family forest landowners control 70 percent of southern forests, the combination of acceptable wood production and better ecosystem services from naturally regenerated pine-dominated stands should present opportunities for a subset of those interested in multiple resource values.