Types of Garden Enemies
SPRING CANKERWORM (Paleacrita vernatd). This species winters in naked brown pupae in soil close to the trees, and the moths appear in any warm spell in February or March. The male has dull gray wings, but the female, gray with a dark stripe down the abdomen, is wingless and has to crawl up tree trunks to lay her eggs under loose bark scales. These hatch as the leaves unfold, and the worms start feeding while still very small. They are green or brown or nearly black, with a yellowish stripe, about an inch long when full-grown. They inch along in a looping habit, bracing themselves with 2 pairs of prolegs, and hang down on silken threads when disturbed. They feed voraciously for about a month, then pupate in the soil; there is only one generation. In years of peak abun- dance you can actually hear the caterpillars eating and are sure to collect them on your clothing while walking along the street.
Fig. 22

FALL CANKERWORM (Alsophila pometaria).
The moths climb trees in the fall to lay their eggs, but these hatch at the same time as spring cankerworms. The moth does not have a dark stripe down the back, the larvae have 3 pairs of prolegs instead of 2, and there are 3 narrow white stripes along the sides above the spiracles as well as the yellow stripe below.

Control. Banding trees with balsam wool covered with sticky tangle- foot was formerly practiced to prevent the females from ascending trees to lay eggs. But unless the band was in place early in the fall and the sticky surface renewed in February it did little good. And even if a tree has been properly banded, young caterpillars on their silken threads can balloon over from an unhanded tree in the neighborhood. Spraying is far more efficient. Apply DDT, 2 pounds 50% wettable to 100 gallons, or lead arsenate, 4 pounds per 100 gallons, with a power sprayer when trees have their leaves nearly expanded. This is most needed in seasons when cankerworms are at the peak of their cycle; in other years spraying can be omitted without too much impairment of tree vigor.

CORN EARWORM (Heliothis armigerd)
also known as tomato fruitworm, tobacco budworm, and cotton bollworm. This caterpillar is generally distributed but is especially devastating in the South. The moth lays eggs on corn silks, and the larvae feed downward, following the silk into the ear. When full grown they are nearly 2 inches long, yellowish or greenish brown with lengthwise dark stripes




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