Blueberry Gall Midge – Dasineura oxycoccana

Blueberry Gall Midge: Appearance, Territory, Damage and Life Cycle Latin Name: Dasineura Oxycoccana Appearance: The adult is a little reddish fly that measures around 1-3 mm in length. The larvae are tiny, white to orange, and difficult to spot with the naked eye. Legless, flat to cylindrical, and tapering at both ends, the larva has no legs and yellow to red in color, mature larvae are about 1 mm length and 0.3 mm broad. When the eggs are placed, they are colorless, but as they grow, they become yellow, orange, or reddish before hatching. Host Plant: The blueberry gall midge is a significant pest of planted blueberries in Florida and other Southeast blueberry-growing areas. It feeds on rabbiteye (Vaccinium virgatum Aiton) and southern highbush (Vaccinium Corymbosum and V. darrowi hybrids) blueberry bushes and grows on them. Territory: The blueberry gall midge is found in the northern United States (Maine, New Jersey, Michigan, Wisconsin, and Washington), where it attacks blueberry and cranberry vegetative buds (Vaccinium macrocarpon Aiton). Midge populations harm both floral and vegetative buds of blueberry in southeastern Georgia, southern Mississippi, and Florida. The blueberry gall midge has been seen on blueberries in the Pacific Northwest recently. Damage Caused: Within two weeks of infection, flower buds dry up and disintegrate. The extent of the damage varies from year to year, although it is usually severe during mild winters and in more southern areas. Vegetative meristems can also be infected, destroyed, or injured, leaving just a few deformed leaves and extremely short shoots. Even while new growth flushes continue throughout the summer in Florida, little harm occurs after mid-May. Damage severity varies from field to field as well. Life Cycle and habits: The midge spends the winter in the soil as a pupa. In the spring, when blueberry plants are putting forth new vegetative growth and leaf buds, adults appear. Each year, the blueberry gall midge has many generations that overlap. Shortly after emerging, females’ mate and then fly to blueberry plants in search of good egg-laying places. Eggs range in shape from cylindrical to oval and are barely 14 mm long. A female may lay several eggs in a single leaf bud, and each bud can hold eggs from multiple females. Adults only survive one or two days. For around ten days, a larva will eat on a blueberry plant. When the larva is fully formed, it leaves the plant, falls to the ground, and pupates beneath the soil surface. The life cycle of the blueberry gall midge might take two to three weeks throughout the summer, but it can take longer in the winter.