Friday, August 7, 2009: 8:20 AM
Acoma/Zuni, Albuquerque Convention Center
Dean H. Gjerstad, Longleaf Pine Stand Dynamics Laboratory, School of Forestry and Wildlife Sciences, Auburn University, Auburn University, AL, Rebecca J. Barlow, School of Forestry & Wildlife Sciences, Auburn University, Auburn University, AL, John C. Gilbert, Longleaf Pine Stand Dynamics Laboratory, School Forestry and Wildlife Science, Auburn University, Auburn University, AL and John S. Kush, Longleaf Pine Stand Dynamics Laboratory, School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL
Background/Question/Methods The first European settlers in what is now the southeastern United States were confronted with an upland forest that was dominated by this one tree species-- longleaf pine (Pinus palustris Mill.). The pre-historical fire regime, both lightning and Native American-ignition, in the longleaf pine ecosystem was characterized by frequent burning, producing fire of low-moderate intensity. These fires were usually non-lethal to the dominant vegetation and maintained the forest structure of a herbaceous understory with scattered shrubs and an open-canopy. These fire-maintained forest ecosystems were essentially two-layered, consisting of a high canopy dominated by mature longleaf pine and an understory of grasses and herbs. The forest was “gappy” as a result of fires of differing intensities and openings created by the deaths of one or several trees which then seeded in with fire tolerant longleaf seedlings in good seed years. The understory was occupied primarily by grasses and forbs, particularly wiregrass (Aristida stricta), bluestems (Andropogon species), other grasses, and a variety of legumes.
Results/Conclusions
Grazing has been a part of the southern U.S. landscape since settlers arrived from Europe. They learned early that fire was the tool needed to maintain the open, grass-dominated understory in the longleaf forests. Prescribed burning became a common management practice on much of the South's rangeland and forest land. It improved the productivity of forested range for both livestock and wildlife. Numerous studies have reported on the importance of burning for maintaining the productivity and quality of the native forage plants to produce cattle gains. What most of the studies have failed to do was to report on the forage available from various overstory densities. The U.S. Forest Service's Regional Longleaf Growth Study will be used to evaluate forage production under various canopy densities. The study has maintained a series of overstory densities for nearly 45 years with a known fire history. This study takes place on the Escambia Experimental Forest in southern Alabama, USA which had a history of studying forest grazing 40-50 years ago. It examines the forage opportunities available under different overstory densities as well as determines the forage available during the growing season and in between the prescribed burning intervals. With increased economic pressures, a decrease in the demand for wood products from U.S. forests, and a renewed interest in restoring longleaf pine ecosystems to the southern landscape, cattle grazing is making a return to southern forest lands.
