Increasing Our Knowledge of Small Woody Biomass Harvesting

Research to support national forest planning

The Warm Springs Ranger District on the George Washington and Jefferson National Forest. Photo by U.S. Forest Service.
The Warm Springs Ranger District on the George Washington and Jefferson National Forest (GWJNF). Photo by U.S. Forest Service.

U.S. Forest Service research helped the George Washington and Jefferson National Forests move forward in implementing a new forest plan by setting up studies to address stakeholder concerns about the effects of harvesting for biomass feedstocks.

The Lower Cowpasture Restoration and Management Project proposed for the Warm Springs Ranger District and the George Washington and Jefferson National Forests has involved multiple public meetings and field trips over the last 18 months.

During this period, stakeholders representing the West Rock mill in nearby Covington, Virginia, suggested that some of the timber sales planned for the large-scale, multi-resource project include additional biomass removals to help fuel a state-of-the-art biomass boiler installed at the mill in 2013 to supply its energy needs.

As the plan moved forward through the comment period, some members of the public expressed concerns about the possible effects of removing additional biomass from harvest areas. This led to the proposal to set up research studies to evaluate the effects of biomass removal. Specific concerns included possible impacts on soil productivity, water quality, and plant and animal ecology.

GWJNF’s Jeff Matthews leading a field tour for stakeholders interested in the Lower Cowpasture project. Photo by U.S. Forest Service.

Dana Mitchell, project leader of the Forest Service Southern Research Station Forest Operations Research unit, responded by setting up research studies to address concerns about biomass harvesting effects. “This newly available market for biomass provides an opportunity to study biomass harvesting as part of the ‘shelterwood with reserves’ treatment proposed in the Lower Cowpasture Project,” said Mitchell. “There’s a need to understand both the operational costs and environmental impacts of biomass harvesting in this project area and others.”

The Lower Cowpasture plan proposes to start harvesting in early 2016. Before harvest, researchers will collect data from study plots installed in the harvest area on downed woody materials and soil disturbance to compare with after-harvest data. During the harvest, researchers will collect data on production rates, the machines used in harvesting, machine costs, and the composition of chips produced from harvested materials. After-harvest activities include a stand damage assessment and biomass chip nutrient analysis.

“Biomass removal is new for the Forest, and currently there is limited research literature for us to use to help explain some of the environmental effects from this type of harvesting,” said Thomas Bailey, forest soil scientist for the George Washington and Jefferson National Forests.  “The Lower Cowpasture project provides an excellent opportunity for Forest Service Research and a National Forest to partner together to improve the current knowledge about biomass harvesting for everyone.”

For more information, email Dana Mitchell at

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