. Cirtus fruits under irragation. Citrus fruits; Fruit-culture. §28 UlrKU^ l^RUlTvS IN GULF-COAST STATES 15 Over a large part of its area of distribution, the cloudy- winged white fly occurs mixed with the common citrus white fly. As was said before, the eggs of the cloudy-winged white fly hatch about 2 weeks after the eggs of the common white fly. It would seem that by delaying the spray application for the common white fly 2 weeks, one spray application could be made to suffice for both the common white fly and the cloudy-winged white fly.^ Such spraying, however, while economical, is not th
. Cirtus fruits under irragation. Citrus fruits; Fruit-culture. §28 UlrKU^ l^RUlTvS IN GULF-COAST STATES 15 Over a large part of its area of distribution, the cloudy- winged white fly occurs mixed with the common citrus white fly. As was said before, the eggs of the cloudy-winged white fly hatch about 2 weeks after the eggs of the common white fly. It would seem that by delaying the spray application for the common white fly 2 weeks, one spray application could be made to suffice for both the common white fly and the cloudy-winged white fly.^ Such spraying, however, while economical, is not thorough in its results and should not be resorted to, especially in the spring when the growth of the insects is very rapid. As soon as the eggs of the common white fly hatch the larvas develop rapidly and by the time the eggs of the cloudy- winged white fly have hatched the larvas of the common white fly are about ready to pass into the pupal stage. In the pupal stage the insects are so resistant that many of them will not be killed by the oil. It also happens that in mixed infes- tations the cloudy-winged white fly does less damage than the common citrus white fly, so it is imperative to control, at the most vulnerable period in its life history, the pest that does the most damage. If, however, it is desirable to economize in the application of sprays and make one spray answer for both species, the best time to spray is in the fall. Growth of the insects is not so rapid in the fall on account of the weather being cooler. When the spray is applied after the cloudy-winged white fly has hatched, the larvas of the common citrus white flies will not be so fully developed as to be wholly resistant to the oil sprays. In cither case, sjoring or fall, it is far better, if lasting results are to be obtained, that the spray be a])|)liod when each insect can be combated most Fig. 14. Please note that these images are extracted from scanned page images that may have been di
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Keywords: ., bookcentury1900, booksubjectcitrusfruits, booksubjectfruitcultur
