In Oregon, huge swaths of the Willamette National Forest, perhaps as much as 12,000 acres, has stands of trees less than 40 years old that have never been thinned. The firs are crowded together, making it hard for sunlight to reach them. Competition for resources has made them susceptible to insects, disease, blowdowns and snow breakage. Trees that should be 13 to 14 feet apart are suffocating just eight feet from their neighbors.
