3 (1 = rare 5 = annual)

3 (1 = very little damage 5 = plants killed)

The squash bug (Anasa tristis) is a perennial and severe pest of pumpkins and squash; it rarely injures cucumbers and melons in the Midwestern United States.

Vegetable

• Pumpkin (Cucurbita pepo; C. maxima; C. moschata; C. mixta)
• Summer Squash (Cucurbita pepo and Cucurbita maxima)

Squash bug adults are brown, flat-topped, and 3/4 inch long. The nymphs are gray, flattened, and up to 3/4 inch long. The eggs are reddish brown and laid in clusters on the leaves.

Both the nymphs and adults suck sap out of leaves, stems, and fruit of squash and pumpkin. Feeding by large numbers causes vines to turn brown and black and then dry up. Heavy feeding on the fruits causes them to collapse and be unmarketable.

Adults overwinter in nearby debris.

Crop rotation will reduce squash bug numbers. Remove debris in the fall to reduce overwintering sites. Treat when the first eggs begin to hatch, usually between June 15 and July 15, if infestations exceed 1 to 1-1/2 egg masses per plant. Treat when squash bugs are young because registered insecticides are not very effective against older nymphs and adults.

Home, Yard & Garden Pest Guide
The Home, Yard & Garden Pest Guide (C1391) provides is written for homeowners and other residents and provides nonchemical and current chemical recommendations for controlling pests associated with trees, shrubs, turf, flowers, groundcovers, vegetables, fruit, and houses. In addition, you'll find detailed information about integrated pest management, pesticide safety, and pesticide application and calibration techniques. This publication may be purchased at your local University of Illinois Extension Unit office, or by calling 800-345-6087, or by placing an order online (search for "C1391").
Visit site >>

U of IL - Distance Diagnosis through Digital Imaging
A free plant, weed, insect and disease identification service available through your local University of Illinois Extension office. Center Educators or State Specialists review & respond to information and digital images submitted by local Extension office personnel. Some samples may require further examination or culture work (nominal fee involved) at the U of IL Plant Clinic.
Visit site >>

U of IL - Plant Clinic
Services include plant and insect identification, diagnosis of disease, insect, weed and chemical injury (chemical injury on field crops only), nematode assays, and help with nutrient related problems, as well as recommendations involving these diagnoses. Microscopic examinations, laboratory culturing, virus assays, and nematode assays are some of the techniques used in the clinic.
Visit site >>