Squash Bug

Anasa tristis

Content coming soon for this insect guide.

Insect Profile

Beneficial Rating

-5 Pest

Active Months

JanFebMarAprMayJunJulAugSepOctNovDec

US Distribution

NortheastSoutheastMidwestSouthwestWestPacific Northwest

Habitat Preferences

gardensagricultural fields

Taxonomic Group

Bug

Order

Hemiptera

Family

Coreidae

Lifecycle

The squash bug life cycle consists of three stages: egg, nymph, and adult. In the spring, overwintering adult squash bugs emerge to feed, mate, and lay eggs. Females lay clusters of around 20 bronze-colored, oval eggs on the undersides of leaves. In southern regions, they may lay 2-3 batches of eggs, while in northern regions, they typically lay only one. The eggs hatch in 7-10 days. The nymphs go through five instars, or stages, over a period of 4-6 weeks. The first instars are light green with black appendages, and they become progressively grayer with each molt. The full nymphal stage lasts about 33 days. One generation is produced each year, though a partial second generation may occur in warmer climates.

Overwintering Strategy

Adults hibernate in leaf litter, under rocks, and in other sheltered places.

Native Range

North America

Attracted By

squashpumpkinswatermeloncucumbersBlue Hubbard squash

Repelled By

nasturtiumtansy

Organic Control Methods

Organic control of squash bugs focuses on prevention and manual removal. Early in the season, check plants for eggs and crush them or scrape them off the leaves. Adult bugs and nymphs can be hand-picked and dropped into a pail of soapy water. Traps can be created by placing boards or newspaper in the garden overnight; the bugs will congregate underneath and can be collected and destroyed in the morning. At the end of the season, clean up all garden debris to eliminate overwintering sites for the bugs. Crop rotation is also a key preventative measure. Some squash varieties, such as Butternut, Royal Acorn, and Sweet Cheese, are more resistant to squash bugs.

Companion Planting

Planting nasturtiums and tansy around squash plants is recommended as a deterrent for squash bugs.