deposits one egg in each chamber. The larvae feed on the nut 
meat until full grown, then they cut exit holes through the shell. 
Most of the larvae vacate the nuts in the fall in northern areas, 
but some may remain in them until the following spring. Full- 
grown larvae enter the soil, usually within 2 or 3 inches of the 
vacated nut, and burrow down to depths ranging from 14 inch to 
1 foot, where they form cells in which to pupate. Here they usu- 
ally remain in diapause for 1 to 2 years, depending upon the 
species, before pupation begins. Newly-emerged adults fly im- 
mediately to acorn-or nut-bearing trees. 
Curculio adults are light tan to brown, or red and reddish- 
brown to black; they are densely clothed with hairs, and range in 
length from 4.2 to 13 mm. The beak is long and slender, some- 
times longer than the body in the female, but always shorter than 
the body in the male. The antennae are 11-segmented, elbowed, 
long, and slender; they are inserted into the beak near its middle 
in the male; in the female, they are inserted near the middle or 
near the base. 
The pecan weevil, Curculio caryae Horn., ranges from New 
York to Iowa and south to Georgia, Oklahoma, and Texas. The 
adult is dark reddish-brown and is from 7.5 to 12 mm. long. The 
female beak is slightly recurved and longer than the body; the 
male’s is only slightly more than one-half as long as the body. 
Adults appear in late summer, and the female deposits several 
eggs in a single nut. The larvae, only two or three of which sur- 
vive, devour the entire contents of the nut within a month. Ma- 
ture larvae vacate the nuts, enter the soil, and remain there until 
the second summer after entry before they pupate. Heavy tree 
losses are often incurred in commercial pecan and hickory nut 
orchards. In some pecan orchards, up to 65 percent of the crop 
has been destroyed. 
The large chestnut weevil, Curculio caryatrypes Boheman 
[=proboscideus (Fab.)], and the small chestnut weevil, C. sayz 
(Gyll.) [=auriger (Casey) ], were important pests of American 
chestnut before the latter disappeared from the American scene. 
Now, they are troublesome only in plantations of Asiatic chest- 
nuts (106, 732). C. neocarylus Gibson feeds exclusively in hazel- 
nut. Several other species feed in the nuts of various hickories 
and pecan. 
Several other species of Curculio breed in the acorns of a large 
number of oaks: C. sulcatulus (Casey) in nearly all species 
within its range; C. pardalis (Chittenden) in 19; C. orthorhyn- 
chus (Chitt.) in 18; C. longidens Chitt. in 11; and C. humeralis 
(Casey) in 10. 
The genus Conotrachelus Dejean also contains a number of 
species important as pests of acorns, nuts, and fruit. The adults 
resemble adults of the genus Curculio. They differ, however, in 
having shorter and less curved beaks, in having the body scaled 
on the upper surface, and in having the breast grooved for recep- 
tion of the beak. Life histories are also similar to those of the 
Curculios, except that Conotrachelus adults appear in the fall and 
spend the winter in the ground litter (288). Gibson (289) pub- 
lished keys to the larvae, pupae and adults of acorn-infesting 
species. Schoof (642) discussed the species occurring in the 
North Central States. 
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