Apple Maggot: Appearance, Territory, Damage and Life

Latin Name: Rhagoletis Pomonella

Appearances: The mature apple maggot is black with white bands on the abdomen and is slightly smaller than a house fly. Males have three white bands on their blunt abdomen, while females have four abdominal bands with a pointed abdomen. Both sexes have a zigzag black band pattern on their wings.

Host plants: Apple (Malus spp.) and hawthorn (Crataegus spp.) are the main hosts of the apple maggot; sweet cherry (Prunus avium) and sour cherry (Prunus cerasus) are also important hosts in two states in the United States.

Territory: The apple maggot (Rhagoletis Pomonella) is an eastern North American native fly that used to feed on hawthorn trees. It became a significant apple pest in the Northeast, and while it is mainly an occasional concern in the South, it may be extremely devastating when large populations emerge.

Damage Caused: Flies lay one or more eggs beneath the apple skin’s surface. As rot progresses, the egg-laying area will eventually become sunken and darkened. The larvae burrow into the fruit (unlike codling moth which feeds primarily in the core area).

Life Cycle and Habits: Hundreds of eggs can be laid by a single female fly. Larvae feed for three to four weeks after hatching. The larvae turn into pupae in the soil when apples fall to the ground. Pupae hibernate during the winter and emerge as adults the following summer.

As a pupa, the apple maggot spends the winter in the soil. Adults begin to emerge from the soil in late June or early July. Throughout the summer, apple maggot flies emerge from the soil and might stay active until October. The adult apple maggot feeds for 7 to 10 days after emergence, until it reaches sexual maturity. Females lay eggs slightly beneath the epidermis of the host fruit after mating. Over the course of her lifetime, which might last 30 days or longer, a single female can lay between 300 and 500 eggs. Depending on the temperature, eggs hatch between 3 to 10 days. While digging into the apple flesh, the larvae (maggots) eat. In most cases, larvae develop in about 30 days. The rate of development and survival of larvae is influenced by temperature and fruit hardness. Full-grown larvae exit the fruit and pupate in the soil.