US Forests

http://www.scientificamerican.com/article.cfm?id=us-forests-soak-up-carbon-dioxide

U.S. Forests Soak Up Carbon Dioxide, but for How Long?

Forests play a key role in offsetting U.S. emissions of greenhouse gases, but that ability may shrink as the climate changes

By Douglas Fischer and The Daily Climate October 18, 2010

The findings, released last week, estimate the nation's expanding forests sequester an additional 192 million metric tons of carbon annually due to increases in both the total area of forest land and the amount of carbon stored per acre.

That's the equivalent of removing about half the cars on the roads nationwide, or almost 135 million vehicles.