THE SAN JOSE SCALE AND ITS CONTROL. ri 
the adult males emerge and fecundate the females, which in turn 
reach maturity and begin the production of young in from 33 to 40 
days from birth. An individual female may give birth, on the 
seasonal average, to about 400 young, and as the life cycle of the fe- 
male covers but a few weeks there may be several generations a year, 
the number varying according to latitude. The progeny from one 
parent during the season have been estimated at 1,608,040,200 
females. It is thus easy to understand how the insect can so quickly 
destroy the plants infested and why prompt remedial measures are 
sonecessary. With the approach of the cool weather of fall, breeding 
Fig. 6.—Enlarged view ofa group of San Jose scales. (Original.) 
eradually ceases and the scales in all stages enter hibernation. Most 
of the older and also most of the younger individuals perish during 
the winter, the survivors being those about one-third or one-half 
grown, as stated. 
MEANS OF DISTRIBUTION. 
The San Jose scale is distributed from one region to another prin- 
cipally on nursery stock, scions, or budding and grafting material. 
The danger of its dissemination in this way is fully realized, and laws 
are in force in the majority of States requiring the inspection of 
nurseries and the destruction of infested stock. Traffic in nursery 
produce is permissible only under the certificate of an official ento- 
