THE CODLING MOTH ON PEARS IN CALIFORNIA, 25 
SECOND-BROOD LARV. 
Time of hatching.— July. 12 was the date of first hatching of larve 
at the laboratory. These were from eggs deposited the night of July 
3. As several adults had emerged and died previous to this date, it 
was not the actual beginning of the egg-laying period. Second-brood 
larve were hatching in numbers July 18 to 20. 
On July 7 careful search in the field showed 5 very young larve. 
From July 10 to 12 second-brood larve were plentiful; from July 15 
to 18 they were numerous, and by this time their work was showing 
a great deal on the unsprayed trees. Occasionally 3 and 4 entrance 
holes were found in a single pear. 
Development of larve in relation to fruit.—The first picking of pears 
in the orchard where the spraying experiment was carried out in 
1909 began July 15 and lasted 5 days. During this time young 
larvee were hatching and entering the fruit in numbers in the unsprayed 
block, so that even the earliest first picking of fruit did not wholly 
escape the second-brood larve. In 1910 many second-brood larve 
were in the fruit before the first picking. The second and third pick- 
ings, coming later, are worse injured. The third or last picking 
receives practically the full force of the second-brood larve. In many 
orchards this picking will run 70 per cent wormy. The third picking 
of pears on the unsprayed block in 1909 showed an average of 75 per 
cent wormy, while in 1910 practically all of the pears left on the trees 
in the check blocks were wormy. 
Life of larve in fruit.—The period covered by the life of the larve 
in the fruit was not positively determined for a very large number of 
second-brood larve. The harvesting of the fruit takes a large per- 
centage of the larve to the packing shed before they reach full 
development. 
At the laboratory several hundred individual records were started, 
but the quick rotting of some of the fruit during a short absence 
destroyed part of the records. The first larve left the fruit August 
6, 1909, at the laboratory, but in the field comparatively few larvee 
as a rule reach their full development before the fruit is all harvested, 
which is about the middle of August. In the summer of 1910 the 
first full-grown larve of the second brood were found at Suisun July 
26, and at Walnut Creek on August 1. At-this time practically all 
pears around Suisun and about two-thirds of the crop in the vicinity 
of Walnut Creek had been harvested. 
Records for 63 individuals which went through in sound or nearly 
soured fruit out-of-doors at the laboratory in 1909 are given in Table 
IX. As may be seen, this gives about 26 days for the period of the 
larvee in the fruit. 
79397°—Bull. 97, pt 2-113 _~ 
