Forest Fire Control Applications
There are approximately 10,600 Primary Base Series maps covering the lands administered by the Forest Service. The Center collaborates with Regional and Forest geometronics personnel to keep these maps current and revises 1,400 of the maps annually, using the 1:24,000-scale topographic map series as a base. Over 2,000 orthophotos are produced each year at 1:24,000 scale, as a layer to the Primary Base Series mapping system.
Secondary Base Series maps, produced at a scale of one-half-inch per mile, cover all or part of a National Forest. There are about 350 maps in the Secondary Base Series of which about 50 are revised each year. These maps serve as administrative planning maps and as a base for preparing Forest Visitor Maps and other products.
Digital elevation models (DEM's) are also produced at the Geometronics Service Center. A DEM gives accurate and consistent elevation data for a Primary Base Map at a density of one elevation every 30 meters.
Cartographic feature files consist of all features appearing on the Primary Base Series maps, except the contours, digitized to meet the accuracy standards of the 1:24,000-scale maps. The revision cycle is 5 years, or about 2,000 maps per year.
Forest Fire Control Applications
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