Wednesday, August 4, 2010

PS 49-12: Recruitment and Dominance of Quercus rubra and Quercus alba in a previous Oak-Chestnut Forest from the 1980s to 2008

Miranda D. Redmond, University of Colorado, Boulder, Rebecca B. Wilbur, University of Virginia, and Henry M. Wilbur, University of Virginia.

Background/Question/Methods

The purpose of this study is to understand how the abundance of the two dominant species, Quercus rubra (northern red oak) and Quercus alba (white oak), in a previous chestnut-oak forest in the Southern Appalachians has changed since the 1980s and may change in the future. Using spatially explicit data from the early 1980s and current data from 2007-08 of individually mapped trees on two plots on Salt Pond Mountain in southwest Virginia, this study looks at how the basal area and density of all tree species has changed, with specific attention to recruitment, growth, and mortality patterns of Q. rubra and Q. alba. Results/Conclusions

Since the 1980s there has been an increase in the number of shade tolerant trees, primarily Acer pensylvanicum (striped maple), and a decrease in number of shade intolerant trees and intermediate shade tolerant trees including both Q. rubra and Q. alba.  A correlation analysis of A. pensylvanicum abundance, Quercus seedlings, and light availability shows a negative relationship with abundance of A. pensylvanicum and light availability in the understory as well as Quercus seedling abundance. Both Q. rubra and Q. alba have experienced stand thinning, and the previous oak-chestnut forest has transformed to an oak-maple forest and will continue to become increasingly dominated by maples and other shade tolerant species.