Codling Moth

Codling moth, Cydia pomonella, is one of the most serious insect pests of apple in the United States.

Biology and Life History

Adult moths are approximately 10 mm (⅜”) in length, with a wing span of 18 mm (¾”).  Wings are mottled gray with a distinctive copper-colored band at the tip of each forewing (Figure 1)

Female moths lay flat, oval eggs singly on developing fruit or adjacent leaves.  Newly hatched larvae enter fruit, usually through the …

Can kaolin clay sprays reduce insect damage to apple fruit?

Yes. Kaolin clay (formulated commercially as Surround WP®) has been shown to be effective against several orchard pests, including apple maggot, white apple leafhopper, and pear psylla. It generally gives at least fair control of plum curculio and several species of fruit pest caterpillars (codling moth, oriental fruit moth, tufted apple bud moth, lesser appleworm). However, university trials also show that heavy use is harmful to beneficial species, and can lead to a flare up of European red mites or …

Dogwood Borer and Apple Trees

The dogwood borer, Syanthedon scitula (Harris) (fig. 1), is from the Family Sesiidae, the family of clearwing moths. Adult clearwings are colorful, day-flying moths that bear close resemblance to wasps. Although they cannot sting, this mimicry no doubt protects them from birds and other predators. They live in all parts of the United States east of the Rocky Mountains.

Figure 1. Adult dogwood borer moth. Photo: Henry W. Hogmire, Jr., West Virginia University.
Adult dogwood borer moth. Photo courtesy of Henry W. Hogmire, Jr., West Virginia University.

The dogwood borer has been considered an …

Burr Knots on Apple Trees

Burr knots are root initials that appear on the aboveground portion of the apple tree trunk. Some rootstocks, such as M.7, M.9, M.26, MM.106, and MM.111, are more prone to developing burr knots than others. Conditions that favor burr knot development include low light, high humidity, and temperatures between 68°F and 95°F.

Burr knots are problematic in a couple of ways. They can be an entry point for organisms, such as dogwood and plum borers, woolly apple aphids, fire blight …

Woolly Apple Aphid

The woolly apple aphid, Eriosoma lanigerum (Hausmann), is a reddish brown insect covered with a white wax mass produced by specialized dermal glands. This wax mass gives the insect its characteristic woolly appearance (fig. 1). The woolly apple aphid is distributed worldwide.

The most important form of injury caused by woolly apple aphids is root injury, consisting of galls at feeding sites (fig. 2). This root injury can reduce the growth of young apple trees; mature trees are affected to …