โ Scribed by John W. Cary
No coin nor oath required. For personal study only.
The possibility of protecting an orchard against cold by enclosing it under a screen cover was studied in a preliminary field test. At the onset of freezing temperatures, water was sprinkled on the screen, forming a continuous sheet of thin ice. The screen and ice cover effectively reduced heat loss from the experimental enclosure. Simulated twig temperatures were 2ยฐ--10ยฐC warmer inside the enclosure during a variety of weather conditions, with outside air temperatures as low as -20ยฐC. When outside air temperatures were -5ยฐC, the inside simulated twig temperature could be held above the critical level for even tender blossoms by briefly sprinkling water under the screen at 10-to 15-rain intervals. Although a screen cover and sprinkler system would be expensive to install, it could provide excellent cold protection and would be less expensive to operate than conventional orchard heaters and wind machines. Cooler daytime temperatures under the screen suggest the additional possibilities of dormancy control and reduced evapotranspiration.
๐ SIMILAR VOLUMES
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