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field test is, as set forth in the Guidelines, to determine that the test 
complies with the Guidelines and presents no significant risk tc health or the 
environment. 
3.2 Need for the Proposed Action 
Classical methods of frost control have many problems. Sprinkler 
Irrigation of leaves for frost control requires large amounts of water and is 
Ineffective when wind or poor sprinkler coverage prevents continuous wetting of 
the plants. The other methods (heating, mixing air layers, furrow irrigation) 
require large amounts of energy and water and are rapidly becoming 
prohibitively expensive. Artificially generated fogs can create safety 
hazards, and burning large quantities of fossil fuels can adversely affect 
environmental quality. (0) 
svrinqae and IE. herbicol a , the so-called "ice-nucleatlon bacteria," 
normally live on plant leaf surfaces. Several scientists have found that these 
bacteria nucleate formation of ice crystals on the leaves when the 
temperature drops a few degrees below freezing. The ice crystals damage the 
plant. Such frost damage is a significant problem for fruit and vegetable 
growers and has a direct impact on the prices that consumers pay for these 
foods. If the bacteria are absent or if the very same bacteria having defects 
in the genes responsible for ice nucleation (which are called the "ice- 
nucleatlon" genes) are present, ice crystal formation occurs at a lower 
temperature. This means that the plants can survive colder temperatures 
without frost damage. Thus, if the normal bacterial population of the leaves 
could be replaced by bacteria that lacked the "ice-nucleatlon" genes, frost 
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