Strawberry bud weevil (Clipper)
Anthonomus signatus Say 
(Coleoptera: Curculionidae)


Adult is a snout beetle about 1/10 inch (3 mm) long, chestnut brown in color, and possessing two black spots on its back (elytra). Larvae are tiny creamy white-colored grubs found inside unopened flower buds.

Biology and damage:

The strawberry bud weevil is probably one of the most important direct pest of strawberries in the United States. This pest has been shown to cause yield losses from 50 to 100% in some areas (Schaefers 1981). The strawberry bud weevil is widespead and occurs throughout virtually all the strawberry-growing regions of this country, including Virginia (Anderson & Walker 1937, Davidson & Lyon 1987). Strawberry bud weevil has one generation per year. Overwintering adults emerge early in the season from ground litter commonly in wooded areas and migrate to strawberry fields (around late April in the Mid-Atlantic region). Ovipositing females puncture unopened buds with their long beaks and deposit a single egg into the bud. Damage results when females sever the strawberry bud from the pedicel following oviposition, causing it to hang by part of the stem, or fall to the ground (Annonymus 1972), thus, preventing fruit formation. Larvae develop in the severed buds and reach maturity in 3-4 weeks. Adults emerge in June, feed on flower pollen, then enter an estavation in mid-summer and remain inactive the rest of the season.

Field scouting/monitoring:

One method of field scouting involves sampling weevils on plants, during the early blossom/bud stage. Shaefers (1981) suggests an economic injury level of 1 female beetle per 40 row feet. Cooley & Schloemann (1990) developed a sampling program using bud damage as a sampling index. According to this program, sample units of 2 row feet of plants are sampled at 5 to 10 locations along a v-shaped transect. Treatment is advised if an average of 0.6 clipped buds per row foot are found.


Recent research in New York indicates that only rows near block edges near woods may need to be sprayed. If compensatory varieties such as Seneca are used, sprays may not be needed at all.

Virginia home spray guidelines 
California guidelines 
Pistillate varieties of strawberries are relatively immune from attack since only varieties with staminate flowers seem to provide adequate food for developing larvae (Davidson & Lyon 1987). Early-fruiting varieties are more susceptible to attack than later-fruiting varieties. Schaefers (1981) recommends topping of plants and removal of foliage and mulch immediately following harvest, then applying a follow up chemical spray to kill overwintering adults. Other cultural practices include avoiding field site selection near wooded areas to prevent high numbers of overwintering adults from entering the field in the spring. Mulches and full canopy beds encourage adults to overwinter and remain in the field, thus plowing of old beds immediately following harvest causes adult mortality. Cropping fields less than three years is also recommended. 

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