CHESTNUT PESTS 
in all probability it is considerably more 
extensive than above stated. 
Lesser Chestnut Weevil 
Balaninus rectus Say. 
The lesser chestnut weevil has the 
scape of the antenna longer than in the 
preceding species and the first joint long- 
er than the second. The average length 
of the body is about one-fourth of an 
inch, but the size varies, as in all of 
these insects. 
The distribution of this species extends 
from Canada and Massachusetts to North 
Carolina, Tennessee, and Ohio, and prob- 
ably farther westward. 
The larvae is only a third of an inch 
long and its length is about three times 
its width. The body is milk-white and 
the head light brownish yellow. 
Life History of Both Species 
The life history is similar for both 
species. These, as well as related nut 
and acorn weevils, hibernate in the lar- 
val condition and in the soil. Both make 
their appearance with the first blooming 
of chestnuts. The beetles increase in 
number as the nuts approach maturity, 
or until about the middle of September 
or a little time before the nuts are first 
marketed. Then they may be seen in 
greater abundance, several pairs, fre- 
quently of both species, often occurring 
on a single bunch of burs. From exam- 
ination of many burs it is deduced that 
the first eggs deposited are laid (seldom 
and very sparingly) in the soft, woolly 
material surrounding the forming nut; 
but later they are inserted in the kerne! 
just under the inner skin, and occasion- 
ally they are deposited somewhat more 
deeply. In no case has the egg been 
found in the outer husk. 
Eges are laid singly, but many are 
placed in a single nut, as high as 40 or 
more (of the smaller weevil) in import- 
ed nuts, and as many as 9 in native nuts. 
By the end of September or the first 
week of October the beetles disappear. 
At about the same time, when the nuts 
first fall, the larvae begin to mature and 
issue from round orifices which they 
gnaw through the shell. 
On leaving the nuts they burrow into 
809 
the earth to depths varying from 2 to 
about 8 inches, according to the hard- 
ness of the soil. The larval period prob- 
ably lasts from three to five weeks in the 
nuts, and about ten months in the earth. 
The beetles do not fly readily, but cling 
tightly to their resting place or drop 
when disturbed; yet, as their bodies are 
not heavy and their wings strong, they 
are obviously able to cover considerable 
distances especialy with the wind. Or- 
dinarily, however, they are sluggish, like 
most other weevils, and probably do not 
go far from the vicinity of the trees 
which have sheltered them as larvae, al- 
though they undoubtedly migrate when 
food is scarce. 
Natural Enemies 
A. natural enemy of the nut weevils is 
known, a small four-winged wasplike fly, 
the braconid parasite Urosigalphus ar- 
matus Ashm., which develops in the body 
of the larva. 
Methods of Control 
The most practical remedy for nut 
weevils that can be suggested is the 
early destruction of the “‘worms” in the 
nuts by means of bisulphid of carbon and 
the observance of clean orchard manage- 
ment and other cultural methods. 
The Water Test of Infestation 
Having doubts of the efficacy of this 
old-fashioned test of the difference be- 
tween “wormy” and healthy nuts, an ex- 
periment was made by the writer with 
native chestnuts obtained from a street 
vender. To begin, 40 per cent were ob- 
viously “wormy,’ and only 60 per cent 
apparently sound. 
Results of Water Tests with Native 
Chestnuts 
NUTS WHICH ROSE TO SURFACE 
Per Cent 
Uninfested 2... 0. ccc eee ees 10 
Showing minute marks only; good 
flavor: salable .... 0 . 2... ce wee wees 20 
Containing full-grown grubs.......... 10 
Containing immature grubs......... 60 
NUTS WHICH REMAINED ON BOTTOM 
Per Cent 
In perfect condition... .......0c000. 40 
Slightly imjured 2... ...0. cee ecw ees 30 
Badly infested 
Completely filled with grubs......... 10 
As will be seen from this experiment, 
noticeably wormy nuts, as evidenced by 
