Scientists from the University of Wisconsin-Madison and the University of Minnesota at Morris are studying aspen trees. Aspen trees are one of North Americas most widespread trees and these studies show that rising co2 in the last 50 years have boosted their growth rates by 50%. These findings are an important role in regulating climate and decreasing greenhouses gases. Aspen trees are called "foundation species" meaning they have a strong influence over other plants and animals around them. In North America aspen trees are very dominant. In Canada they cover 42 million acres and 6.5 million in Wisconsin and Minnesota. With them being so dominant this growing rate could have unknown ecological consequences. In the western United States do not seem to be responding quite the same. This is seen to be from the extended period of drought. They took trees ranging from 5 to 76 years old and compared their tree-ring data to previous records. With this they are able to look at the increase of growth with the change of chemistry in the air. Researchers have found that aspen grow a lot faster to elevated carbon dioxide unlike other tree species.
