8 FUMIGATION OF APPLES FOR SAN JOSE SCALE. 
remembered that the young crawling San Jose scale is comparatively 
fragile and quite susceptible to unfavorable conditions, and the 
chances would be greatly against it even were the described condi- 
tions present, very improbable in themselves. 
Danger of infestation in this way would be limited practically to 
fruit on the market in. late summer or early fall, as allowing a suffi- 
cient time before cold weather for the insect to become about one- 
third grown, since most individuals younger than this die during the 
winter, as well as those much older. Ordinary winter varieties of 
apples, as Ben Davis, York Imperial, Baldwin, Greening, etc., come 
on the market in cool climates so late in the season as to practically 
eliminate them as possible disseminators of scale under out-of-door 
conditions. | 
The history of the spread of the scale in the United States is of © 
interest in this connection. The insect was present in California for 
years before its introduction into the East occurred. Much scale- 
infested fruit. was unquestionably sent to various eastern markets, 
and thus unlimited opportunity was offered for its introduction in 
this way. Its actual establishment, however, so far as known, was 
brought about only by means of infested nursery stock received from 
a locality in California where the insect was abundant. 
The foregoing remarks apply particularly to fruit consumed in the 
fall or early winter. If the fruit is held for any time in cold storage, 
the chances arg still more increased against the insect’s successful 
establishment. Holding the fruit for any considerable time in cold 
storage, in a temperature of from 30° to 32° F., results in the death 
of the younger individuals and older ones, especially those in a 
breeding condition. The survivors, as in the case of the insects under 
_ winter conditions out of doors, are mostly those about one-third grown, 
and the percentage of these which survive rapidly decreases with 
continued holding in cold storage. Hence, after the insects are 
again brought under favorable conditions, several weeks are required 
for them to reach a reproductive age, and the fruit exposed to warm 
temperatures for a necessary time for the development of the scales 
would most certainly become badly deteriorated, if not actually 
decayed, thus resulting in the premature death of the insects. In 
practice, fresh fruit is perhaps never held so long in a warm tem- 
perature before consumption. The probability of the young scales 
being able to continue development to maturity on fruit parings, etc., 
is scarcely to be considered, since this refuse would quickly decom- 
pose or dry. 
The gradual dying of scales on fruit held in cold storage, during 
1906-7 and 1907-8, is indicated in Tables II and XI, as determined 
at different times for comparison with the condition of scales on 
fumigated fruit. In the later examinations the live insects found 
were exclusively those about one-third grown. 
