College of Agriculture & Natural Resources

• Green fruitworm

  Immature larvae of the green fruitworm (GFW) feed on flower buds and new foliage.

• Pear rust mite

  The overwintering stage is a light brown, wedge-shaped adult, which cannot be seen without a 15X hand lens. The summer forms are nearly white in color, and even smaller than the overwintered adults.

• Lesser appleworm

  The adult is a small gray moth with distinct small orange bands or patches on the wings; some blue is also evident in newly emerged specimens.

• 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.

• Pale apple leafroller

  The adult is elongated and dull gray. The larva is creamy white with an amber head, which turns black in the penultimate instar.

• Armillaria root rot

  The bark at the crown and roots sloughs off easily, exposing the dense white growth of the fungus. The growth extends in a fan-like pattern underneath the bark. Black shoestring-like strands may be obvious on the surface of the bark.

• Obliquebanded leafroller

  Adult wings are beige, tinged with red. Forewings are crossed with oblique brown bands. The female is larger than the male. The green eggs are laid in masses on the upper surface of leaves.

• Apple red bug

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

• 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.

• 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.

• Verticillium wilt

  Leaves wilted or browned on one or several branches, often remaining attached; the rest of the tree appears healthy. Young trees are often killed by infection.

• 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.

• Mineola moth (Destructive pruneworm)

  Adult is a bluish gray moth that assumes a wedge shape when at rest. It has a transverse broad white stripe bordered by a smaller reddish brown stripe in the middle of the forewings a smaller set of similar bands occur near the posterior edge.

• Stink bugs

  The adult has an oval shield-shaped body, grayish or brownish in color; a spur is present on each side of its thorax. Eggs, grouped in masses of 20 to 30, are in the shape of small barrels. They are gray, cream or gold-colored, decorated by a ring of small hairs.

• European brown rot

  Monilinia laxa is a plant pathogen that is the causal agent of brown rot of stone fruits.

• Powdery mildew of cherry

  The fungus attacks young leaves and shoots and tends to cause more damage on sour cherry than sweet cherry. Infections appear as white circular lesions or patches of powdery growth on either side of the leaf or on the terminal ends of shoots.

• Western flower thrips and flower thrips

  Western flower thrips and Flower thrips are indistinguishable without a microscope. Adults are slender and yellowish, with short antennae; the wings are long and narrow, and held over the abdomen.

• X-Disease

  This disease is caused by a mycoplasma and infects many varieties of stone fruits. On cherry, infected trees tend to develop a dieback and a generally unthrifty appearance. Infected trees decline, but the rate of decline is dependent on the rootstock.

• Spring cankerworm

  The adult male is gray and has winding lines on its forewings the female has stumpy gray wings. The larva is pale green to dark brown with two yellow longitudinal bands on the sides. It moves in a looping inchworm fashion.

• Cherry fruit flies

  The adult cherry fruit fly is somewhat smaller than the house fly, with a yellowish brown head and legs, and white crossbands on the abdomen. The black cherry fruit fly is slightly larger and its abdomen is entirely black.