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Abstract
The interception of rain and snow in the forest-canopy is a factor of sufficient magnitude to require its measurement in any complete study of the hydrology of forested watersheds. In experiments set up to measure the relations of watershed-runoff and infiltration to precipitation it is particularly essential to measure net rainfall reaching soil under the forest-canopy, rather than total precipitation, in order to estimate adequately the amounts of water available for runoff.
Citation
Johnson, W. M. 1942. The interception of rain and snow by a forest of young ponderosa-pine. Transactions, American Geophysical Union. 23: 566-570.