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Abstract
Measurement of precipitation on forested experimental watersheds presents difficulties other than those associated with access to and from the gages in all kinds of weather. For instance, the tree canopy must be cleared above the gage. The accepted practice of keeping an unobstructed sky view of 45" around the gage involves considerable tree cutting. On a level area, trees 30 feet tall around a gage require an opening of about 0.06 acre, and trees 60 feet tall, 0.25 acre; on slopes, the openings required can be much greater. Once cleared, the opening immediately begins to close - almost surreptitiously - so that periodic maintenance is necessary.
Citation
Leonard, Raymond E.; Reinhart, Kenneth G. 1963. Some observations on precipitation measurement on forested experimental watersheds. Research Note NE-6. Upper Darby, PA: U.S. Department of Agriculture, Forest Service, Northeastern Forest Experiment Station. 1-4
