Lesser Appleworm: Appearance, Territory, Damage and Life Cycle

Latin Name: Grapholita Prunivora

Appearance: The Lesser Appleworm is a tortricid moth endemic to eastern North America that has spread across the United States and most of Canada. LAW has been found to attack plum, cherry, apricot, pear, and peach in addition to apple. Adult LAW moths are gray-brown moths that look a lot like oriental fruit moths but are smaller (approximately 1/3-inch (8mm) length with 7/16-inch (10.5mm) wingspans) and have more brown patches visible on the wings. Pupae are a golden-brown color. Larvae are around 3/8 inch (9.5mm) long, pinkish white, and nearly similar to OFM larvae. The eggs are white to yellow ovals that are approximately 1/50 inch (0.5mm) in diameter and are placed singly.

Hosts Plants: The Appleworm favors the fruits of rose plants. Its primary host is the hawthorn. It most likely contaminated the fruits of hawthorn, native plums and crab apples, shadbush, wild cherry, and wild rose before apple and other deciduous fruits were brought to North America.

Territory: The lesser Appleworm is a tortricid moth endemic to eastern North America that has spread to the United States and most of Canada. LAW has been found to attack plum, cherry, apricot, pear, and peach in addition to apple.

Damage Insect Cause: Apple, plum, and cherry are all targets. Larvae excavate huge shallow mines beneath the fruit skin and may tunnel deeper as they age, but not into the core. Feeding harm in the fall is frequently restricted to the calyx.

Life History and Habits: LAW overwinter as larvae in tree trunk cracks and detritus. Adults emerge and mate around petal fall after pupating in the spring, depositing eggs on leaves or fruit. These eggs develop into little larvae that feed just beneath the skin of the fruit. They pupate and emerge as second-generation adults in July and August after complete development. As late as October, these adults produce eggs that hatch and penetrate fruit. Every year, there are normally two generations (and occasionally a third).

It spends the winter as a mature larva at the base of host plants or behind bark scales. Adults emerge in April, and females deposit eggs on the fruit’s surface or on the leaves. The larvae feed on the fruit for around three weeks before pupating near the tree’s base or under bark scales. Adults of the second generation arrive in late April. These, too, deposit their eggs on the fruit. Mature larvae construct cocoons to overwinter late in the season.