INSECT ENEMIES OF EASTERN FORESTS 287 
foun also in Washington and Idaho, and is spreading to other areas. 
It attacks willow, alder, poplar, and birch. : 
This insect hibernates as a partly grown larva in the sapwood. 
When plant growth is resumed in the spring the larvae develop 
rapidly, and pupation takes place in June. The adult beetles are 
found in July and August feeding on the young shoots. The eggs 
are laid singly or in groups of two to four in slits cut in the corky 
bark, often in scar tissue. The young larvae feed in the soft tissue 
of the inner bark and outer layer of sapwood until cold weather. 
In the spring feeding is resumed, the boring usually proceeding 
around the branch or stem, and often causing girdling. When ready 
to pupate the full-grown larva bores upward and inward, and con- 
structs the pupation cell in the center of the stem. 
Injury by this weevil is often very serious. All poplars and willows 
over a year old are subject to attack, and recently planted trees and 
nursery stock are particularly susceptible. The base of the tree is 
usually most seriously affected. Where basket-willow culture is prac- 
ticed the monetary loss at times is considerable. Slender-stemmed 
species are not attacked in any degree, probably because of the small 
diameter of the stems and twigs. In the forests of the Northwest, 
where willow is an important ground cover and game browse, exten- 
sive areas are being destroyed. 
A penetrating oil emulsion sprayed or wiped on the affected parts 
of the tree during the first period of warm weather in the spring 
will kill the larvae, as they are then close to the surface of the bark. 
Carbolineum emulsion has proved very satisfactory, but it should not 
be allowed to reach the roots. Very badly infested trees, or the most 
seriously infested branches, should be cut and burned before early 
summer. For discussion of other applicable measures see page 26. 
Several other species of Cryptorhynchus, such as C. parochus 
(Hbst.), C. bésegnatus (Say), C. fuscatus (Lec.), and C. fallax (Lec.), 
have been collected from hardwoods. C. fallax commonly breeds in 
hickory killed by the hickory bark beetle. Apteromechus ferratus 
(Say) sometimes does great damage, killing sassafras trees up to 10 
inches in diameter. It has been found from New York to Florida. 
The white-fringed beetle (Pantomorus leucoloma ( Boh.) ),a native 
of South America, has very recently been introduced into Florida, 
Mississippi, Louisiana, and Alabama. Since 1936 the adults have 
been found feeding on more than 50 species of plants and the larvae on 
20 species. Although it is primarily considered as a larval pest on 
agricultural crops, the adult has been observed feeding on the foliage 
of pecan, hackberry, black gum, poplar, blackjack oak, hawthorn, and 
sassafras. The feeding by the adults, however, is of minor impor- 
tance, as compared with the damage by the larvae, which feed on 
the stems and taproots of crop plants. Injury to tree species by the 
larvae has not yet been reported. 
The female beetle is robust, about 12 mm. long, dark gray, with a 
lighter band along the margins of the elytra and two paler longitudinal 
lines on each side of the thorax and head. The body is densely covered 
with pale hairs, those on the elytra being longest. The true wings are 
rudimentary and the species cannot fly. So far as is known there are 
no males, and reproduction is parthenogenetic. The oval-shaped eggs 
are about 1 mm. long and are deposited in masses, usually of from 15 
792440°—49—_19 
