THE SAN JOSE SCALE AND ITS CONTROL. 5 
NATURAL HISTORY AND HABITS. 
The San Jose scale passes the winter in an immature condition 
fixed to the bark of the host plant, the small dark-gray or blackish 
scales being just discernible with the unaided eye. In early spring, 
with the ascent of the tree’s sap, the growth of the scale begins, 
and early in April, in the latitude of Washington, D. C., the small, 
two-winged, active males issue from the male scales. After mating 
with the females the males die. The females continue to grow and 
in about a month begin the production of living young—minute, 
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Fic. 4.—Appearance of apple orchard badly infested by the San Jose scale; many of the limbs and branches 
have been killed. (Author’s illustration.) 
yellow, oval creatures which by very close observation may be dis- 
tinguished without the aid of a hand lens, crawling here and there on 
the infested plants in an effort to find a suitable place for settlement. 
The young insect is active for some hours, but soon settles, pushes 
its slender, threadlike beak into the plant, and begins to feed by suck- 
ing out the sap. After this there is no further movement from place 
to place, and the waxy covering, which often begins to develop before 
the insect has settled, soon covers it completely. 
In about 12 days the insects molt, and from this time on the male 
and female scales may be readily distinguished. From 8 to 10 days 
later the males change to pupx, and in from 24 to 26 days from birth 
