Controlling solar light and heat in a forest by managing shadow sources
1974
Halverson, Howard G. | Smith, James LeRoy
Control of solar light and heat to develop the proper growth environment is a desirable goal in forest management. The amount of sunlight and heat reaching the surface is affected by shadows cast by nearby objects, including trees. In timbered areas, the type of forest management practiced can help develop desired microclimates. The results depend on the size and orientation of openings created and on the shade cast by surrounding vegetation. A computerized method to calculate the extent of boundary shading. for any combination of date, slope, and aspect between 23.45° N. latitude and 50° N. latitude is described. For those who do not wish to develop their own, a set of shadow-length tables is available upon request. These may be secured as an entire set or by individual latitudes. They provide coverage for the contiguous United States in increments of 2° from 36° N. latitude to 50° N. latitude. By extrapolation, the tables can be used from the Mexican to the Canadian border.
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