14 BULLETIN 571, U. S. DEPARTMENT OF AGRICULTURE. 
THE LARVA STAGE, 
During the season of 1913 eggs were found to hatch from about the 
middle of May until the last days of July, and during the season of 
1914 and 1915 from the latter part of May until the first few days 
of August. The period over which the eggs are hatching depends, 
of course, upon the time of emergence of moths, and it will be noted 
in Tables I, II, and III that there was some variation in the issuance 
dates of adults during 1913, 1914, and 1915. When the young larvae 
gnaw their way out of the eggshells they commence feeding upon the 
portion of leaflet immediately adjacent to the place where oviposition 
occurred. Throughout the summer and during the early fall the 
larvae feed very sparingly upon the foliage, and as they extend their 
feeding quarters they enlarge the little winding or spiral cases which 
afford them protection. Although the larvae may feed for nearly three 
months or even longer in some instances, they hardly attain a length 
greater than six one-hundredths of an inch. During the latter part 
of September these larvae begin to seek hibernating quarters around 
the buds, where they construct small, compactly woven, oval hiber- 
nacula, and by the middle of October practically all larvae will have 
left the foliage and may be found snugly protected in the hibernacula. 
These little "worms" very wisely abandon the compound leaves upon 
which they have been feeding, just a short time before the foliage 
begins to drop in the autumn, in order to attach the winter cases 
securely to the buds and twigs. 
The larvae remain in hibernation until the latter part of March 
or the first days of April, at which time the buds on pecan trees 
usually begin to open. Just as the buds are opening, the larvae emerge 
from their hibernacula and attack the unfolding leaves. The perni- 
cious feeding habits of the larvae at this time result in serious injury 
to the foliage and in greatly reducing the yield of nuts. During the 
year 1913 the larvae reached full growth from about April 20 until the 
latter part of June, but the majority pupated between May 10 and 
June 10. During the seasons of 1914 and 1915 the majority of the 
larvae were about a week to ten days later in reaching maturity. 
NATURAL ENEMIES. 
Three species of birds — the blue jay (Cyanocitta cristata), the mock- 
ingbird (Jlimus polyglottos) , and the orchard oriole (Icterus spurius) — 
have been observed feeding upon the larvae of the pecan leaf case- 
bearer. These birds, as well perhaps as those of other species, do 
much to check the ravages of this pest, and their protection in the 
pecan orchard should be encouraged. The blue jay very likely is 
more beneficial than harmful to the pecan grower. In the writer's 
opinion the good that this bird does in feeding upon injurious pecan 
