The raspberry fruitworm (Byturus unicolor) is a type of fruitworm beetle in the Byturidae family. It is also known as the western raspberry fruitworm and fruitworm beetle. Adults are 4-5 mm long, small yellowish-brown oval shaped beetles. The larvae are white with darker areas on the top of each body segment and develop in the berries of various Rubus plants. When the larvae reach maturity, they drop to the ground, burrow into the soil and pupate. Adult beetles overwinter in the soil and emerge in the spring feeding on fruit buds, young leaves and flowers.
Although the adult feeding will cause injury to leaves, the larvae cause more damage. Early season symptoms can be observed in the foliage (a tattered appearance due to feeding). Excessive feeding by adults may cause leaf “skeletonization” resulting in a weaker plant. Numerous adult beetles may destroy entire flower clusters. Larval tunneling through receptacles can cause loosening of berries and falling fruit before harvest. Contamination of harvested fruit by larvae can be a serious problem.
There are natural solutions to the raspberry fruitworm.
For more information contact your local BioBee field agent.