CLEVELAND, Dec. 14 (UPI) -- U.S. biologists say although oak forests may be approaching extinction, lightning fires might play a vital role in their regeneration.
Case Western Reserve University Assistant Professor Paul Drewa and graduate student Sheryl Petersen suspect such fires might provide a natural mechanism to deter encroachment of shade tolerant hardwoods that are crowding out oaks and other plants on the floors of forests across the eastern United States.
Drewa and Petersen examined weather patterns to see if environmental conditions exist for the occurrence of lightning fires in the Appalachian forests of southern Ohio.
"Human alterations to the natural fire regime, especially decades of fire suppression, have changed oak-dominated ecosystems in southern Ohio and throughout the eastern United States," reported Petersen. "As a result, there is a preponderance of shade tolerant hardwoods that are preventing oaks and other native species from regenerating."
The researchers say oak canopies of remaining forest fragments are deceptive and the trees are not thriving well beyond the seedling stage.
"Eventually this means the demise of oak trees and other less shade tolerant plant species in future years," said Drewa.
The research appeared earlier this year in the Journal of the Torrey Botanical Society.