Persistent, Pesky Squash Bugs

September 06, 2018

Squash bugs hatching Bayside garden possEPOD (16) (1)

SquashBug_IMG_9006 (1)

Photographer: Rob Sheridan 
Summary Author: Rob Sheridan 

Squash bugs (Anasa tristis) are ubiquitous true bugs -- insects with piercing-sucking mouthparts to feed on plant sap. Although they don't carry disease, they're a bane to squash and pumpkin gardeners. In the late spring and early summer, adults that have overwintered in nearby hiding places (such as garden debris) find and feed on young plants in the family Cucurbitaceae, harming the plant by depriving it of nutrients. After mating, females lay a cluster of 10 - 30 tiny (1.0 mm x 0.5 mm), gold-bronze colored eggs on the underside of healthy leaves. Pale-green first-instar nymphs (1.0 - 2 .0mm) emerge after 10 - 14 days. They quickly darken and begin feeding, transitioning through 4 additional instars, looking progressively like the adult bug. The first photograph shows the first-instar nymphs emerging from their eggs. Note that the earliest to emerge already darkening. The second photo shows an adult squash bug, perhaps scouting for an overwintering site nearby so the cycle can continue. Photos taken in eastern Massachusetts on August 12, 2017.

Photo Details: Top - Camrea: NIKON COOLPIX AW120; Software: Windows Photo Editor 10.0.10011.16384; Exposure Time: 0.0040s (1/250); Aperture: ƒ/4.4; ISO equivalent: 250; Focal Length (35mm): 56. Bottom - Camera: Apple iPhone 5s; Exposure Time: 0.0010s (1/977); Aperture: ƒ/2.2; ISO equivalent: 32; Digital Zoom Ratio: 2.655x; Focal Length (35mm): 77.