the winter. Feeding is resumed in the spring. The larvae usually bore around the 
branch or stem. When ready to pupate, the larvae bore upward and construct cells in 
the center of the stem. There is one generation per year. 
The first evidence of attack is the occurrence of dead patches or cracks in the bark 
on the trunks of small trees or on the branches of larger ones, and the presence of 
small holes chewed in the bark. The wood under these patches eventually becomes 
honeycombed with larval tunnels. Branches and small trees may be completely 
girdled, or so badly weakened by tunnels that they break. All poplars and willows 
over 2.5 cm in diameter are subject to attack, especially recently planted trees and 
nursery stock (530, 1096). 
The genus Conotrachelus, like the genus Curculio, contains a number of species 
important as pests of acorns, nuts, and fruit. The adults of Conotrachelus resemble 
those of Curculio, but tend to be smaller. They have shorter and less curved beaks, 
the body is scaled on the upper surface, and the prosternum is grooved for reception 
of the beak. 
Probably the most economically important species is the plum curculio. C. 
nenuphar (Herbst). It breeds in plums, cherries, peaches, apples, and other fruits. 
This weevil is a serious pest in commercial orchards, where repeated applications of 
insecticides are required during the first growing season for control. A number of 
insecticides are registered for use. The quince curculio, C. crataegi Walsh, is also 
a pest in orchards. It attacks quince, pear. peach, and hawthorn fruits. Some races 
of this species that attack apple have been found (8/3). 
There are three acorn-infesting species in the United States. C. naso LeConte can 
be distinguished from the other two by the absence of femoral teeth: C. carinifer 
Casey has prothoracic punctures larger than elytral punctures: and C. posticatus 
Boheman has prothoracic punctures that are not larger than those on the elytra 
(477). 
Conotrachelus naso occurs from Maine to Florida and west to Minnesota in the 
Eastern United States. It has been bred from acorns of 16 species of oaks. The adult 
is shiny black to light reddish-brown. Light and dark scales make varied patterns on 
the elytra and thorax. White scales usually make four spots on the thorax and base 
of the elytra and a band on the distal third. Adults are from 4.8 to 6.6 mm long. The 
snout is moderately stout and curved, and longer than the prothorax. It is slightly 
longer and less stout in the female than in the male. Adults emerge from April to 
August, depending on locality. Eggs apparently are deposited in damaged. cracked, 
sprouted. or previously infested acorns. The larvae mature in 2 or 3 weeks. Then 
they vacate the nuts and enter the soil to pupate. New adults emerge about 1” to 3 
months later. 
Conotrachelus carinifer occurs in the Coastal States from New Jersey to Texas 
and west to Arizona. It has been reared from the acorns of eight species of oaks. 
The wing covers are dark reddish-brown with a few black areas. These are covered 
with brown to white setae in patches and bands. The prothorax is black and clothed 
in pale-brown to white setae. The beak is curved and longer than the prothorax in 
both sexes. Adults emerge in late summer or early fall and begin laying eggs within 
4 days. The larvae become mature and vacate the acorns within 12 to 18 days. 
Conotrachelus posticatus occurs throughout much the same range as C. naso. It 
is known to breed in acorns from nine species of oaks. The adults have dark reddish- 
brown wings with black splotches, the black sometimes predominating. The elytra 
are sparsely covered with pale tan, yellow, and white setae with some patches. 
Usually there is a narrow, curved posterior band. Their bodies are 4 to 5 mm long. 
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