. Better fruit. Fruit-culture. 1915 BETTER FRUIT Page 41 The San Jose Scale Insect, Etc, Continued from last issue The San Jose scale differs from other scale insects in being many-brooded during the summer. Other scales â with which it would be confused have but a single generation each year. In the Northwest a common scale insect is the oyster-shell bark louse. This long and narrow insect, several times larger than the San .lose scale, over-winters in the egg condition to hatch in early summer. The oyster-shell scale is mainly abundant in Western Washing- ton and in those orchards of Eastern
. Better fruit. Fruit-culture. 1915 BETTER FRUIT Page 41 The San Jose Scale Insect, Etc, Continued from last issue The San Jose scale differs from other scale insects in being many-brooded during the summer. Other scales â with which it would be confused have but a single generation each year. In the Northwest a common scale insect is the oyster-shell bark louse. This long and narrow insect, several times larger than the San .lose scale, over-winters in the egg condition to hatch in early summer. The oyster-shell scale is mainly abundant in Western Washing- ton and in those orchards of Eastern Wasliington at an elevation above 1,800 feet. Cottonwood trees are often afflicted with a scale known as Aspidi- otus ancylus, which is almost indis- tinguishable from the San Jose scale. Oranges are sometimes received in- fested with another similar scale known as Aspidiotus aurantii, but as the scales of the citrus fruits cannot thrive on the deciduous fruits of the North, they need not be a cause for alarm. Fortunately the San Jose scale can be quite easily controlled. It readily suc- cumbs to applications either of oil sprays or of sulphur-lime. Normally, a great many individuals die through the agency of internal parasites or of such carniverous insects as the Lady Bird beetles; some die of inclement weather or through inability to obtain a foothold when first born; many die from the poison they themselves de- velo|) in their food plant; but such deaths can be considered in no wise as reducing the danger from this pest. Summer spraying has never proved adequate, for a spray strong enough to destroy the old, heavy-shelled females will injure the foliage. During the dor- mant season trees will withstand a rela- tively strong application of spray, and for this reason, as well as for the fact that most of the individuals to be de- stroyed are the scarcely protected young, winter spraying has come into general custom. Since the insects occur so largely at the ends of branches
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