Strawberry Bud Weevil: Appearance, Territory, Damage and Life Cycle

Latin Name: Anthonomus Signatus

Appearance: The strawberry bud weevil, Anthonomus Signatus, is a weevil that is a major pest of strawberries in North America. It is also regarded to be a significant pest of raspberries. It is indigenous to North America. Adult strawberry weevils’ range in color from brown to black, with big dark dots on their wing coverings. They are snout beetles that are little more than 110″ long. Strawberry weevil larvae are white legless grubs that live within strawberry, raspberry, or blackberry blossom buds. They are generalists that feed on the pollen of their hosts. When present in large numbers, weevils shred the pedicels of unopened flower buds on strawberry, blackberry, and raspberry plants, inflicting substantial damage. The strawberry weevil may damage up to 75% of the crop in some locations.

Hosts Plants: Strawberries (Fragaria Ananassa)

Territory: North America and some areas of Europe

Damage Insect Cause: Strawberry damage is more likely to occur when strawberries are cultivated near woodlots or other appropriate hibernation areas. Clipping begins in early May, and producers should carefully inspect their fields for the first symptoms of damage at that time. To see if a pesticide treatment is required, go through random rows of plants, counting the number of clipped buds per linear foot of row. Take five separate 10-foot chunks from different parts of the field. Divide the total number of observed cut buds by the total number of linear row feet assessed. A pesticide treatment is warranted if more than one cut bud per linear row foot is discovered. Pay special attention to fields next to woodlands and hedgerows.

Life History and Habits: Adult strawberry weevils spend the winter under mulch and leaf litter in strawberry, blackberry, and raspberry beds. They become busier around flowering time, when they start feeding on buds and leaves. Females lay their eggs in holes made with their snouts approximately halfway between the center and the tip of a blossom. The bud stem was then cut around 1/4″ below the bud. A single female laid 20-30 eggs. Depending on the weather, the eggs hatch in 6-14 days. Larvae feed on the cut buds and reach full size in 29 days. When the larvae reach maturity, they pupate and emerge as adults (approximately mid-summer). The adults eat for a brief period of time, then hibernate until the following spring.