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Bug of the Week is written by "The Bug Guy," Michael J. Raupp, Professor of Entomology at the University of Maryland.

To squash a squash bug: Anasa tristis


This beauty means trouble for cucurbits.


Green and black squash bug nymphs huddle just after hatching from nearby eggs.

An interesting thing about the English language is that many words have dual meanings.  The Encarta dictionary attached to my word processor defines squash as a noun meaning “vegetable of the gourd family” and as a verb meaning “to crush something with pressure.” Both definitions are directly relevant to this Bug of the Week. Here is what I mean. Squash, zucchini, pumpkins, and gourds are all members of the cucurbit family. Humans are not the only ones that find these prickly plants delectable. In a previous episode of Bug of the Week, we met the dastardly squash vine borer, a caterpillar with the power to wilt even the toughest pumpkin vine. While admiring some squash vines the other day, I noticed several plants with severely wilted leaves and vines. After inspecting vines and finding no evidence of bad borers, I turned over a few leaves and found juvenile and adult stages of squash bugs merrily sipping sap.

Older squash bug nymphs are ghostly white.

Squash bugs are members of the true bug clan, meaning they have an elongated beak for sucking liquid food, wings that are part membranous and part leathery, and, as juveniles, they are known as nymphs. We met other members of this cantankerous clique including bed bugs, brown marmorated stink bug, boxelder bug, and wheel bug in stories past. Both nymph and adult squash bugs consume fluids from their cucurbit hosts and problems arise when dozens of feeding squash bugs jab so many beaks into the vascular system of the plant. Inserting the beak damages the plumbing of the plant. This injury and removal of vascular liquids cause plants to wilt. When squash bugs are abundant, their damage can reduce the bounty produced by your squash and zucchini vines.

Fortunately, there are a few tricks you can use to foil the squash bug’s shenanigans:

  • At the end of the year, rid your garden of decaying vegetation and remnants of vines and leaves. These refuges are used by adult squash bugs to survive the wild winter.
  • In spring, plant varieties such as Butternut, Royal Acorn, or Sweet Cheese that are more resistant to squash bugs.
  • I have spoken to gardeners who place floating row covers over their plants early in the season to help keep these buggers from colonizing their plants. If you go this route, remember to remove row covers when blossoms first appear. If you don’t, then pollinators cannot do their job. No pollination means no pumpkins, squash, or zuccs.
  • If you see squash bugs, squash the squash bugs. Really, if you have just a few plants, it is relatively easy to inspect plants and when you find the golden-bronze eggs, green or whitish nymphs, or tawny adults, crush them.


Squashing eggs of squash bugs is an easy way to derail their dastardly deeds.

  • If squashing squash bugs isn’t your thing, remove them from the plant and drop them into a vessel of soapy water. Squash bugs are poor swimmers and when they have expired their tiny bodies can be placed in the compost heap to nourish your garden next season.  


After enjoying squash bug adults as they dash about your zucchini, you may want to terminate them to avoid problems down the road.


Bug of the Week thanks Anne Marie and Dennis and the marvelous Master Gardeners of Montgomery County who were the inspiration for this episode. To learn more about squash bugs, please visit the following web site: