A few weeks back I was thinking this might be my first ever bug-less garden year. The aphids that bombarded the roses in 2011 just did not show up this spring. My tomato plants were downright gaudy with unblemished leaves and fruit.

The fungus Alternaria eventually showed up and caused blight enough to warrant spraying the tomatoes, but there still had been only minimal evidence of insects. Snap beans, peas, sweet corn, cucumbers, melons, cantaloupe, okra, peppers; none have been treated with any insecticide so far this season. And I should have known it was too good to be true.

The squashes, both yellow and zucchini, and their kinfolk pumpkin vines all withered after getting off to a good start with lush foliage, healthy blooms and early fruit-set. They all croaked. The hollowed out, rotting stems at ground level were sure signs that squash vine borers had done them in.

The squash vine borer is the larval stage of a black and orange moth that looks more like a wasp. This year’s moths came from the ground after spending the winter about 2 inches down. The female moth does what many pregnant insects do; look for a place that will provide food for her babies once they hatch out.

Although the entire vine plant family of vegetables can host borers, the summer squashes and pumpkins are their favorites. I can vouch for that because my squash and pumpkin borer victims were adjacent to cucumbers, cantaloupe and watermelon. And those plants are doing just fine.

Borer eggs are laid on leaves and vines. Once they hatch, the tiny larvae bore into the vines and begin eating away. The reason the leaves wilt is the borers destroy the water carrying structure inside the vines. Eventually the vines rot and collapse. Here in the South, the first set of borers turn into adult moths and the cycle repeats. The second generation of borer larvae goes into the soil to pupate and come out next spring.

This is one of the garden insects hard to control. There is not much to be done with the adult moth. Since the moths are attracted to the color yellow, though, some garden gurus suggest putting out yellow containers filled with water to draw the moths in for drowning. Some claim shaving cream sprayed on the vines will prevent egg-laying and still others advise laying aluminum foil on the ground under vines to repel the moths.

Squash vine borers are among the larvae that will stop eating if they ingest the biological Bacillus thuringiensis, an organic control better known as simply Bt. Some gardeners wipe Bt on squash vines weekly for any larva to get a dose as it bores in. More determined squash lovers actually inject a Bt solution into the vines.

Even more committed to their squash are those who carefully slit vines with a razor blade to look for borers inside. The razor blade is also used to finish off the culprits.

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Terry Rector writes for the Warren County Soil and Water Conservation District, 601-636-7679 ext. 3.