What Bores Holes in Acorn Squash?

Cucumber Beetle

• Cucumber beetles are small, around 1/5 to 1/4 inch in length. They are yellowish orange with black heads and legs. The spotted cucumber beetle has 12 black spots on its wing covers. The striped cucumber beetle has black stripes. Larvae live in the soil and aren't commonly seen.

Life Cycle

• Adults overwinter in plant debris or in neighboring plants or trees and emerge in the spring to feed and lay eggs. Females lay eggs in clusters of between 225 and 800 in the soil. Eggs hatch in five to eight days and larvae feed on roots or on fruit touching the ground. Larvae will feed for about 15 days and then spend six or seven days as pupae. Several generations will grow in a summer.

Damage

• The first generation of adults feeds on seeds and seedlings. Later generations feed on all parts of the plants including vines, stems, leaves and fruit. As they feed on fruit, they bore deep pits into the rind, inviting disease and making the fruit inedible. Larvae damage the plants at the roots, killing them and reducing the amount of water and nutrients available to the vine. This damage results in a weak vine susceptible to disease.

Control

• Inspect your plants regularly for adult beetles and remove them by hand. Wear gloves and squish them or drop them in a bucket of 1 part bleach to 3 parts water. Reduce overwintering sites by cleaning up crop debris and removing weeds. Install mesh row covers as soon as you plant seeds. When the plants begin to flower, remove row covers for a few hours in the morning so pollination can occur. Squash vines are sensitive to chemicals, so avoid using pesticides.