Rascally squash bugs can make a mess of your cucurbits.
Homonyms, words with two or more meanings, are interesting constructs of any language. For example, take bark, it has a couple meanings. It can be the corky tissue protecting the outside of a tree or the vocalizations of furry, four-legged mammals that like trees for, well, you know. My dictionary defines squash as a noun meaning “vegetable of the gourd family” and as a verb meaning “to crush something with pressure.” Let’s look at the first meaning of squash. Squash, zucchini, pumpkins, and gourds are all delectable and nutritious members of the cucurbit family. However, humans are not the only ones that find these prickly plants scrumptious. 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 in a community garden, I noticed several plants with wilted, yellow leaves. A closer inspection failed to find bad borers, however, the leaves of the squash were loaded with immature and adult squash bugs merrily sipping sap.
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 plant’s vascular system. In addition, squash bugs can transmit a nasty bacterium, Serratia marcescens, causing what is known as cucurbit yellow vine disease. These insults 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.
Who doesn’t love pattypan squash? But look out pattypan, those clusters of bronze eggs will soon hatch into tiny green and black squash bug nymphs. As they grow and molt, white wax cloaks their bodies. If you see adults roaming on your cucurbits, or discover eggs and nymphs, snatch them off and dispose of them in whatever way you like.
Fortunately, there are a few tricks you can use to foil the squash bug’s shenanigans:
1) 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.
2) In spring, plant varieties such as Butternut, Royal Acorn, or Sweet Cheese that are more resistant to squash bugs.
Floating row covers placed early in the season may help keep squash bugs and other insects from infesting your crops.
3) 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 zucchini.
Been waiting for the second meaning of squash? 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.
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. Have a squashing good time!
Acknowledgements
Bug of the Week thanks community gardeners of Montgomery and Howard Counties for providing the inspiration for this episode and the backdrops for observing squash bugs.