Effective crop cooling of vineyards was obtained with the use of small amounts of water, intermittently applied through overhead sprinklers. The light sprinkling cooled the air, raised the humidity, and cooled the plants. Sprinklers functioning on 3-minute on and 15-minute off periods cooled the air by 7 to 10 degrees and raised the humidity 10 to 20 per cent. Plant temperatures were reduced 15 to 25 degrees. The cost of this operation was minimal. The true potential is still to be explored.

Instrumentation was made available through a grant to the University of California by the C.R. E. A. (California Committee on Relation of Electricity to Agriculture) for crop cooling and frost protection studies. Equipment for radio control was provided by RACO Manufacturing Company, Berkeley, California.