College of Agriculture & Natural Resources

• Green peach aphid

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

• Blue mold

  Blue mold enters the fruit through wounds, stem-end invasion, or as a core rot. Infection is first visible as a soft and sunken, yellow to pale-brown circular lesion on the surface of the fruit.

• 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.

• Replant disorders

  In general, trees suffering from replant disease show slow and uneven growth within the first three years of planting. Both specific and non-specific replant disorders are known.

• 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.

• Click beetles

  The click beetle is dark-colored its body is hard and elongated it has a characteristic pair of spurs and sometimes colorful markings on its thorax.

• Quince rust

  Attacks only the fruit of apple and pear. Symptoms begin as a purplish lesion, usually appearing on the calyx end of the fruit. As the disease progresses, the entire calyx end becomes blistered and deformed. Tube-like structures eventually form and produce powdery, bright orange spores.

• Root-lesion nematode

  Root-lesion nematodes are microscopic, migratory endoparasites that feed on the root systems of many crops. Affected trees appear stunted, may exhibit chlorosis or yellowing of the leaves, and have poor yields; young trees may be killed.

• 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.

• 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.

• Phytophthora root, crown, and collar rot

  Crown and collar rot are often and mistakenly used interchangeably. Collar rot refers to infection that affects the bark tissue of the scion portion of the tree at or just below the soil line, whereas crown rot affects the bark tissue of the rootstock portion of the tree.

• Skeletonizers

  The adults of the skeletonizers are brown and short, with transverse bands on each forewing. The larvae are yellow to pale green with numerous hairy discs on each segment of the body.

• Stigmaeid/"Yellow" mites

  Agistemus fleschneri is the principal species found in QC and northern ON orchards, while Zetzellia mali predominates in the US, southern ON and the maritime provinces.

• Black rot (Blossom end rot, Frogeye leaf spot)

  Fruit infections that occur early in the season appear at the calyx end and typically develop into blossom end rot that may not appear until the fruit begin to mature.

• Apple mosaic virus

  Young leaves develop pale to bright cream-colored spots, blotches, bandings or patterns as they expand in the spring. These turn brown and become necrotic as they age and premature defoliation may occur when infection is severe.

• 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.

• Southern blight

  Trees attacked by the fungus show a general decline. In the early phase of disease, a dense mat or web of white mycelium is evident at the base of the tree.

• Apple pith moth

  Head of adult is covered with white scales; forewings are narrow, mostly black or dark brown with white marks and usually with an irregular faint, rusty yellow line in the middle, and with two prominent black scale tufts.

• Eyespotted bud moth

  Adult forewings are bluish gray with a central cream-colored band and black spots. The chocolate brown larva has a black head and thoracic shield.