Eastern U.S. forests growing faster

EDGEWATER, Md., Feb. 2 (UPI) -- U.S. scientists say they've found evidence that forests in the Eastern United States are growing faster than they have during the past 225 years.

The Smithsonian Institution ecologists focused on the growth of 55 stands of mixed hardwood forest plots in Maryland. Geoffrey Parker, who has tracked the trees' growth for 20 years, said the plots range in size with some as large as 2 acres. Parker's research is based at the Smithsonian Environmental Research Center, 26 miles east of Washington in Edgewater, Md.

Parker and Smithsonian Tropical Research Institute postdoctoral fellow Sean McMahon said the forest is growing, on average, an additional 2 tons per acre annually. That's the equivalent of a tree with a diameter of 2 feet sprouting up over one year, the researchers said.

Parker and McMahon said their findings suggest the faster growth rate are due to climate change and, more specifically, rising levels of atmospheric carbon dioxide, higher temperatures and longer growing seasons.

The scientists, who said their findings might have significant ramifications in weather patterns, nutrient cycles, climate change and biodiversity, report the research in the Proceedings of the National Academy of Sciences.