Temperate forests play an important role in the sequestration and storage of carbon. We evaluated the long-term effects of manipulating stand density on aboveground live tree carbon dynamics and volume production for separate pine (Pinus spp.) and oak (Quercus spp.) forests of central USA. For both species groups, stand-level carbon storage in standing live trees was greatest without management, with unthinned pine plateauing around 100 Mg/ha of carbon at approximately 50 years old and the oak stands increasing to around 100 Mg/ha of carbon by about 80 years old. In the pine stands, stand-level carbon sequestration was greatest in stands that were thinned but maintained fully stocked conditions. Consequently, the gross carbon that accumulated during the study period, which included standing carbon in live trees and carbon from trees that were harvested or otherwise died, was maximized when stand stocking was maintained at an average of around 80% stocking during the study period. These results were compatible with the production of sawtimber volume, which was greatest for stands that were maintained in fully stocked but not overstocked conditions. Our results demonstrate that thinning can be a forest management strategy to achieve multiple objectives, including those for carbon management and sawtimber production. Study Implications: Our results support stand-density management (i.e., thinning) as a forestry practice compatible with carbon objectives and more traditional objectives of timber production. Aboveground carbon stored in live trees was greatest without thinning, but gross production and sequestration rates were greatest when stand density was maintained in fully stocked but not overstocked conditions. Active forest management during stand development can provide managers with the flexibility to address multiple objectives and may be used with other carbon management practices such as extended rotations or continuous canopy cover, particularly in the central and northeastern United States where forests are generally aging uniformly throughout the region.

Understanding how forests respond to traditional management in the context of climate change is increasingly important for developing multi-objective management strategies. In the Missouri Ozarks, the influence of long-term forest management on climate mitigation and adaptation potential is largely unknown. Using data from two long-term thinning studies, we determined the influence of stand density on carbon dynamics and drought response in the Missouri Ozarks. First, carbon storage and sequestration rates of even-aged short leaf pine and upland oak forests were assessed to better understand the role of manipulating stand density in mitigating climate change. Next, we developed a short leaf pine tree ring-width chronology to determine the influence of thinning on tree-level growth response during a severe drought. Results offer valuable information to land managers regarding the effects of stand density and traditional management practices on mitigation and adaptation to climate change in the Missouri Ozarks.

Abstract Securing oak regeneration is a common management challenge in the central and eastern United States. We quantified the abundance of tree species groups in clearcuts in mid-Missouri more than 30 years following harvest to determine differences in species dominance based on aspect (exposed, protected, or ridge sites). Each tree was classified as “dominant” or “suppressed” based on its relative contribution to cumulative stand stocking, following concepts of the tree–area relation. Although maples or understory species were the most abundant across all sites, oaks and hickories contributed to more than 60 percent of the dominant stems on the exposed sites. In contrast, oaks and hickories made up less than 25 percent of the dominant stems on protected and ridge sites. Results indicate that clearcutting reset the successional trajectory, from a transition to maple dominance to maintaining oak–hickory dominance, on exposed sites but not on ridge or protected sites.