is small, 1/4 inch long, brownish with humps on the wing covers, and a
snout about a third the length of the body. Adults winter in any shelter
around the orchard, fly to trees in spring to feed on buds, petals, and
newly set fruit, then lay their eggs in crescent-shaped slits in developing
fruit. Grayish-white, legless, curved grubs feed in the flesh of the fruit,
then drop to the ground to pupate. Adults appearing in July feed on and
scar the fruit. Fruit invaded when young usually drops; later it remains
on the tree, but is scarred, wormy, and worthless.
Control. Pick up and destroy dropped fruit. The use of DDT on apples
for codling moth control has increased injury from curculios. Some spray
programs now start with lead arsenate, switching to DDT later. Benzene
hexachloride effectively controls plum curculio on plums and peaches
but imparts an off-flavor to the fruit. Lindane, the purified form, is better
but should only be used early in the season. Parathion is used by some
growers, also chlordane. Lead arsenate can be used safened with lime,
at the rate of 2 pounds lead arsenate, 8 pounds hydrated lime to 100
gallons of water. It is applied at petal fall, 7 to 10 days later, and 2 weeks
ROSE CURCULIO (Rhynchites bicolor).
The eastern form is red with a
black undersurface and beak, about 1/4 inch long; some western
forms are all black. The curculio drills holes in rose buds, which either do
not open or have petals full of holes, and then lays eggs in rose hips. It
can be controlled with DDT.
Cutworms are smooth, fat, gray or brownish caterpillars, larvae of
moths. They stay curled up in the soil during the day (Figure 27), but
come out at night to chew off plant stems, newly set seedlings in particular,
at about ground level. There are many species, including climbing cutworms, that feed on all plant parts and subterraneum forms that stay
in the soil and subsist on roots. There are usually one or two generations
a year in the North, several in the South.
BLACK CUTWORM (Agrotis ypsilori),
sometimes called greasy cutworm.
This species moves restlessly from one plant to another, cutting off
many stems as it feeds. The larva is greasy gray to brown with faint
lighter stripes and rounded granules on the skin.