| Many vegetation maps of a remote, high mountain landscape in the Snowy Range of southeastern Wyoming, USA, are too inaccurate for many scientific research or management decisions. This study produces a vegetation map of forest, grassland, shrubland, wetland, and rock by mapping on the ground with GPS, with the premise that this is the most accurate method of producing a map, and that such a map should most accurately represent the land cover. The GPS-produced map is used to assess the accuracies of three existing classified maps, and three maps classified from aerial photography images. The GPS map is also used to evaluate the validity of the assumptions and methods used to interpret the aerial photography and to create the maps. The conclusion is that the three existing maps have moderate overall accuracies, from 38.4% to 50.3%, and that class accuracies for forest, grassland, shrubland, and wetland are low to very low, from 0.2% to 34.9%. The dark pixels in aerial photography do not seem to be the trees. The dark pixels are shadows and water. |
