Hyphantria cunea Drury.
Though a general feeder attacking all kinds of fruit, shade and forest trees, the fall web-worm commonly feeds upon the foliage of nut trees, especially hickories, causing considerable damage in the South. The adult is a white moth, having a wing-spread of an inch or more, appearing in midsummer and laying its egg-cluster on the under side of a leaf. The young caterpillars make a nest at the end of a lateral branch by drawing the leaves together with their webs. These nests usually appear in July and August, though in Connecticut there is a partial second brood and usually a few nests of the early brood may be found in June. In the South there are two complete generations. When the larvae have exhausted their food supply, they extend their nest by taking in fresh leaves, but always feed inside the nest, differing in this respect from the tent caterpillar which makes its nests here in May. When fully grown the caterpillars are about one and one-fourth inches long, with brown bodies covered with light brown hairs, and may be seen crawling about seeking a place to pupate. They soon go into the ground where they transform, the adults emerging the following year.
The best remedies are (1) clipping off and burning the nests when small, and (2) spraying the foliage with arsenical poison.
The Walnut Bud Moth.
Acrobasis caryae Grote?
Inconspicuous nests containing small caterpillars are often found at the ends of the new shoots of Juglans regia, seriously injuring them, and sometimes killing the trees. One small tree two feet high was killed, and thirty-five pupae were found in the nests at Dr. Morris' farm in 1912. The adult is a small gray moth with a wing expanse of about three-fourths of an inch. There are three broods each season in Connecticut, the larvae appearing about June 1, July 10 and August 18.
By spraying the foliage with lead arsenate (3 lbs. in 50 gals. water) this insect can be controlled. One application should be made about June 1, followed by a second about July 10.
Though this insect is thought to be Acrobasis caryae Grote, it is often difficult to distinguish some of these species in this genus without a knowledge of their food habits and seasonal life histories. We possess such knowledge regarding this species which we have studied and reared in Connecticut, but it is lacking in connection with adult specimens in the United States National Museum labeled caryae, which superficially seemed identical with ours. Further study, therefore, may prove this to be an undescribed species. There are other bud-worms attacking nut trees, especially in the southern states, where they cause considerable damage to pecans.
The Walnut Weevil Or Curculio.
Conotrachelus juglandis LeC.