INDIANA – Three months after Hoosier National Forest’s 700-acre Jeffries prescribed burn, data collected shows nearly 1.2 million oak and hickory sprouts (ref. Figure 1).
In the Hoosier National Forest, oak seedlings are present, but are often outcompeted by shade tolerant species such as maple and beech and will not become overstory trees without a disturbance mechanism to allow them to receive enough sunlight. Research has shown that prescribed fire is not only highly effective at doing this, but it is also the most cost-effective method to reduce competition. In a prescribed fire, oak seedling has the competitive advantage of being able to re-sprout and put energy into shoot growth due to energy held in reserve in their large root systems. Use of a helicopter for aerial ignition of prescribed fire leads to a more intense fire as it can be lit more quickly than fires lit by hand, thus reducing the competing trees more successfully.
A portion of the burn - 500 acres - was the very first prescribed fire for oak regeneration that non-profit American Forests has ever provided funding for, and was conducted as a national pilot for similar projects in the future. The Jeffries Burn was a reforestation cost-share partnership between the Forest Service and American Forests. Each organization contributed $15,000 to fund personnel, equipment and a helicopter specially equipped for aerial ignition.
The Jeffries Burn site is part of an ongoing study by the Hoosier National Forest, USDA Forest Service’s Northern Research Station, and Purdue University’s Department of Forestry and Natural Resources. The long-term, repeated measure study is comparing several active management methods (shelterwood harvest, thinning, herbicide treatment and prescribed fire) and their results on oak reproduction.
Oaks are invaluable trees to wildlife, providing food and shelter to hundreds of species. They are also one of the most valuable woods for making furniture, flooring and other wood products, and support an important slice of the 2.4 million jobs in America’s forest products industry. Oaks are a dominant tree species throughout the eastern forest. Historically, they were sustained by natural disturbances and the use of fire by Native Americans. But changing land uses and fire suppression have made the future of oaks less certain. The survival of oak seedlings is challenged in many places by too many deer feeding on them, repeated pest invasions and lack of fires to reduce competition from other tree species. Active management, such as prescribed fire and timber harvest, mimic natural disturbance and is necessary to spur the next generation of oaks.