• Twospotted spider mite

  Adult and nymphal mites are yellowish to pale green with a dorsal pair of apparent dark "spots". Males are smaller than females and have a pointed abdomen. The female takes on an orange tinge in the fall.

• Peach bark beetle

  Adult's body is brown with many punctures, from which arise yellowish hairs. The larva is a small, legless grub.

• Bacterial canker (blossom blast)

  Leaf scars, stomata, and areas of injury are the principal sites of infection. The most conspicuous symptoms are limb and trunk cankers, blossom blast, "dead bud", and leaf spotting; these symptoms may or may not occur together.

• Dogwood borer

  The adult is bluish black with yellow bands and has clear wings, resembling a wasp. Larva is creamy white to pink with a sclerotized reddish head.

• Leaf weevils

  Leaf weevils are green or brown curculios with a metallic appearance. Their antennae are borne on the snout.

• 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.

• Prunus stem pitting

  Affected trees appear weak and show a general decline. Leaves may have upward cupping, turning prematurely yellow or reddish purple, droop, and then prematurely drop. The bark is abnormally thick and spongy and the wood underneath has a severely pitted, indented texture. Symptoms are most severe in the wood just above and below the soil line.

• Cherry leafminer

  The adult is a small, bronzy tan-colored moth, with a wavy darkish brown to black band at the outer third of the forewings.

• Apple red bug

  Adult has head and thorax bright red in color with brown wings.

• San Jose scale

  Adult males are minute, winged insects about 1 mm long and golden brown with a reddish tinge. Scales may be either disk-shaped or oval, and are composed of concentric rings of gray-brown wax radiating from a tiny white knob.

• American brown rot

  American brown rot is common on apricot, peach, nectarine, plum and cherry.

• Rusty spot

  Lesions begin as small, circular, tan to orange blemishes approximately 3–5 mm in diameter. The discoloration is due to discoloring of the fuzz on the fruit.

• European red mite

  Adult female European red mites are less than 0.5 mm and dark red with eight legs. Adult males are smaller than the females and have a pointed abdomen. Males are usually dull green to brown.

• Green pug

  The adult is a grayish moth with mottled or scalloped dark striations toward the wing margins. The larva is a green inchworm with a dark head and a dark reddish brown dorsal mid-line present in later instars.

• 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.

• 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.

• Perennial canker of stone fruit

  Small twig infections are usually found around winter-killed buds, leaf scars, and picking and pruning injuries. They appear as sunken discolored areas with alternating zonation lines and may ooze amber gum unless the twig is killed.

• 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.

• Pear psylla

  Adults resemble very small cicadas and can be reddish brown or tan to light brown. Smaller, wingless nymphs are yellow with red eyes, flat and oval in shape, and develop within a clear honeydew drop.

• Peach scab

  On fruit, lesions begin as small, greenish circular spots that gradually enlarge and darken as spore production begins. These spots appear when fruit are half grown and are most common on the stem end of the fruit, but can occur over the whole surface.