College of Agriculture & Natural Resources

• Alternaria fruit rot

  The disease appears as velvety dark green to black, circular, sunken lesions on mature fruit; the infected tissue is firm and brown. Disease is typically associated with over-ripe or damaged fruit, or fruit held in storage.

• Spotted tentiform leafminer

  The adult is a tiny beige moth with heavily fringed wings striped with golden brown and white bands. Eggs are laid individually on the undersurface of the leaves.

• Green Apple Aphid

  Green apple aphid nymphs and adults prefer to feed on the underside of leaves on growing shoot tips and stems.

• Brown marmorated stink bug

  Brown marmorated stink bug adults are shield-shaped, with mottled brown coloration on the upper and lower surface. They can be distinguished by lighter bands on antennae and they have darker bands on the membrane part of the front wings.

• American hawthorn rust

  Attacks only the leaves of apple and pear; affects the apple varieties McIntosh and Cortland in particular.

• Oystershell scale

  The adult female remains immobile under a small brown scale in the shape of an oyster shell attached to the bark of branches. The white and oval eggs are laid inside the scale and crawlers emerge in the spring during the petal fall stage of apple.

• Black peach aphid

  These smooth-looking, pear-shaped insects have long antennae and a pair of cornicles extending from the posterior end of the body.

• Gypsy moth

  The adult male is brownish and marked with blackish zigzag lines. The adult female is whitish with brown transverse zigzag stripes and does not fly. The masses of oval and yellow eggs are laid on the trunk of trees and covered with hair left by the female.

• Widestriped green fruitworm

  The adult has bluish or steel gray wings marked with inconspicuous mottled patches.

• Gray mold

  Lesions usually start at the calyx or stem end of the fruit or at wound sites as small water-soaked areas. As lesions age, they enlarge, turning from grayish-brown to light brown, and eventually to a darker brown.

• Mucor Rot

  Infected tissue appears light brown, soft, and watery. The infection usually develops at wound sites, at the calyx end, or at the stem end of the fruit.

• European earwig

  The European earwig is dark brown with an elongated body, equipped with pincer-like forceps at the rear of the abdomen. The short elytra do not entirely cover the abdomen.

• Apple maggot

  Adults are black flies with three or four white cross bands on the abdomen, a prominent white spot at the posterior end of the thorax, and the wings are marked with black bands in the shape of an "F".

• Japanese beetle

  Japanese beetles can be present from June through September. Japanese beetle adults are metallic green or greenish bronze with reddish wing covers and several white spots near the abdomen tip and along the sides. Larvae are larger C-shaped grubs that live in the soil.

• Dry eye rot (blossom end rot)

  Symptoms begin at the calyx end of the fruit, causing a reddish discoloration at the site of infection. The rot is at first soft, but eventually dries out, turning tan to brown with a red border.

• Apple seed chalcid

  Adult is a small, dark wasp with a bright green head, thorax and abdomen with coppery or bronze metallic reflections, brownish yellow legs, clear hyaline wings, and a long ovipositor.

• Dusky stink bug

  Stink bug adults have a broad, flattened, shield-shaped body and a narrow head. The dusky stink bug is dark brown, with sharp shoulder projections.

• White peach scale

  Adult female is creamy-white to reddish orange, and covered by a round waxy scale that is grayish to brownish white. Adult males are tiny yellow 2-winged insects, and nymphs are oval and white to orange.

• Green stink bug

  Stink bug adults have a broad, flattened, shield-shaped body and a narrow head. The green stink bug is uniformly grass-green.

• Flatheaded appletree borer

  The adult is a short-horned beetle, flattened above, with short antennae and large conspicuous eyes. The upper surface of the body is dark metallic brown with slightly patterned wing covers.