Blueberry gall midge

Blueberry gall midge larvae feed inside developing flower buds and shoot tips, causing them to swell, distort, and fail to open properly. You will notice abnormally swollen, discolored buds that do not develop into flowers or fruit. Damage appears in early spring as buds begin to expand. This pest reduces fruit set on affected canes in Western Washington blueberry plantings.

Prune and destroy infested buds before larvae mature and drop to the soil to pupate. Maintain clean ground cover beneath bushes to reduce pupation habitat. Encourage parasitic wasps that attack larvae inside the galls. In commercial plantings, targeted insecticide applications at bud swell can reduce first-generation populations.