In 1989, South Carolina’s Francis Marion National Forest lost close to a third of its pine and hardwood trees to Hurricane Hugo. Forest managers have spent the last 30 years recovering from that disturbance and working to meet the state’s growing needs for clean water, forest products, recreation areas and wildlife habitat. To that end, they adopted a new forest plan in 2017 focused on restoring longleaf pine, the once-dominant southern species, across 33,000 acres of national forest lands.
This goal and the management work to implement it are based on research conducted on the Santee Experimental Forest, located on the west side of the Francis Marion. Established in 1937, it’s a 6,100-acre living laboratory that has hosted many long-term studies on the effects of fire, hurricanes and forest management practices on tree growth, streamflow and wildlife communities.
Managers from the forest have teamed up with scientists from the Southern Research Station to study the impacts of replacing existing loblolly pine stands with longleaf pine. Earlier studies suggest that water yield, or the amount of water that leaves a forest and is available for downstream use, may be greater from longleaf pine landscapes than from loblolly pine or mixed pine and hardwood stands. Longleaf pine forests are less dense, with fewer large trees in the canopy and a more open understory than loblolly forests. In a longleaf pine stand, less rainwater is lost through evaporation, allowing more rainwater to seep through the soil to the groundwater.
The study features three treatments in one watershed. In the first treatment, 140 acres of loblolly pine will be harvested, then replanted with longleaf pine seedlings. The second treatment involves thinning 160 acres that have some longleaf pines present. This treatment will retain critical habitat for the red-cockaded woodpecker and encourage natural longleaf regrowth. The third treatment, 50 acres, combines thinning and creating small openings in the canopy.
These treatments will begin in 2019 through a Good Neighbor Authority agreement with the South Carolina Forestry Commission. This agreement will expedite the timber harvest, helping both the Forestry Commission and the local economy.
A year after the harvest, the team will conduct prescribed burns to reduce logging waste and wildfire fuel loads. Longleaf pine planting will take place two years after the harvest and be monitored seasonally and annually. Scientists will develop models from the data collected to simulate future longleaf pine forest conditions. These model projections can be combined with long-term monitoring data to track the progress of the restoration, anticipate potential changes or risks, and adjust management decisions to keep the desired outcomes on target.
Researchers can also use the models to link the Santee project to other restoration efforts in the region—not just in wet pine flatwoods, but anywhere in the South where forest management plans might be informed by landscape-scale forecasts.
The project is an example of strategic, science-based management conducted in the spirit of shared stewardship to meet the shared goals of the national forest and its partners.
SRS manages a network of 19 experimental forests, including the Santee. The Santee project demonstrates how the SRS network can bring together expertise and tools to answer important questions about the sustainability of southern species and their environments.
Forest Service staff from this project are working with Clemson University, College of Charleston, and partner organizations like The Longleaf Alliance and NRCS Soil Carolina to reach local landowners and share technical assistance about restoring, improving and maintaining longleaf pine forests on private lands.