College of Agriculture & Natural Resources

• Green fruit rot

  Both fungi attack the blossoms but rarely invade the twig.

• 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.

• 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.

• Prunus necrotic ringspot

  Individual branches or the entire tree shows delayed budbreak or foliation, stunted wavy leaves, and shortened blossom pedicels in spring. Leaves develop chlorotic spots, lines, or rings as they emerge.

• Roundheaded appletree borer

  Adult has a hard, elongated body, with white and brown longitudinal stripes and long antennae. The larva is a fleshy, cream-colored legless grub with a dark brown head, blackish mandibles.

• Pear slug (Pear sawfly)

  The adult looks similar to a small, black-bodied wasp with the ventral side and legs yellow in color. The larva is small, fleshy, dark green to orange, slug-like, and slime-covered, with the front part of the body enlarged.

• European fruit scale

  The female is immobile and covered with a circular waxy shell that becomes dark gray over time and is elevated at the center. The adult male is brownish red with an elongated abdomen, long antennae and wings.

• Pear midge

  The adult resembles a very small mosquito or gnat; the body is brown and the wings transparent with simple veins. The larva is a white maggot with no legs or visible head; the posterior end is blunt, and the front end tapers to a point.

• Periodical cicada

  Adults are wedge-shaped, nearly black, with red eyes and red-orange wing veins. The clear wings are held tent-like over the body.

• Minute pirate bug

  Adults are very similar in size to the mullein plant bug (Campylomma varbasci), but their head is narrower and their wings are colored contrasting white and black.

• Snowy tree cricket

  Adult somewhat resembles a field cricket, but is pale green in color and has a longer, more slender body and smaller head. Antennae are much longer than the body; males have stiff veins in their flat wings.

• Eastern tent caterpillar

  The adult is reddish brown with two white, transverse-parallel bands. Masses of shiny black eggs are laid in a ring around twigs. Larvae have long silky hairs on their body and a yellow line on their back.

• 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.

• European corn borer

  Adult is a pale yellowish brown moth with irregular darker bands running in wavy lines across wings male is distinctly darker than the female.

• Black knot

  Black knot usually develops over two seasons. The disease first appears in late summer or autumn as an olive-green swelling on new shoots. Disease develops rapidly the following summer, forming a characteristic dark, course-textured warty knot.

• Cherry leaf spot

  Lesions begin as small, circular red to purplish spots on the upper leaf surface. Spots enlarge as they grow older, typically coalescing and turning brown. Lesion centers may eventually drop out to give the leaf a "shot-hole" appearance, particularly on plum.

• Rosy apple aphid

  Populations arise from the overwintered stem mothers, which are wingless and purplish in color, and form into colonies of rosy-purple nymphs with dark cornicles.

• Pear thrips

  Adult is slender and brown, with short antennae and a swelling behind the head; the wings are long and narrow, with fringes of long hairs.

• Cherry fruitworm

  The adult is a small, brownish gray moth with a median gray band on the forewings and a dark spot at the base of the hind wings. Although whitish gray with a black head when young, the larva eventually becomes pink tinted, with a brownish tan head.