@article {3945, title = {Ground verification of Aerial survey for POC root disease}, year = {2002}, pages = {Two page brochure}, publisher = {PNW Research Station, USDA Forest Service, Forestry Sciences Laboratory}, url = {http://www.fs.fed.us/pnw/publications/brochure-misc.shtml}, author = {PNW Research Station, USDA-FS} }