EDIT
This scenario is being replayed across the West. In Colorado, aerial surveys show that from 1996 to 2008 Colorado lost almost 2.5 million acres (1 million hectares) of pine forest to the beetle outbreak, Wyoming 677,000 acres and South Dakota 354,000 acres. Over the same period of time, the spruce beetle, which has also ravaged forests as far north as Alaska, took out 374,000 acres of spruce trees in Colorado and 340,000 in Wyoming.
That cumulative total of over 6 million acres (2.5 million hectares) is an area larger than Israel or South Africa's Kruger National Park. Farther north in Canada, the pine beetle has attacked trees over an area of about 39 million acres (14.5 million hectares) in British Columbia since the 1990s. The sheer scale of the damage can be seen northwest of Denver in Colorado's Yampa Valley. Vast tracts of formerly evergreen forest now have huge splashes of orange running through them.
According to the U.N. Food and Agriculture Organization, a third of the United States' land area is covered in forest but it is only expanding at a rate of about 0.1 percent per year. Under "cap and trade" provisions in the U.S. climate bill, additional forest growth may be encouraged through a market mechanism that will allow reforestation efforts by landowners and other groups to be counted as "carbon offsets." Such projects could generate cash through "carbon credits" paid by polluters who want to exceed their own emissions caps.
A forest can recover, but that can take decades. "Most forests will recover the carbon they lose but if the next 50 to 100 years is important we may not have that much time. It's setting back carbon storage efforts," said Ryan.
EDIT
http://www.reuters.com/article/environmentNews/idUSTRE57300N20090804?feedType=RSS&feedName=environmentNews&pageNumber=2&virtualBrandChannel=0