Gypsy moth control

By CONNIE MERTZ

For those living near woodlands, the gypsy moth is certainly no stranger. In our neck of the woods, the infestation has been far worse than in recent years. A few weeks ago, male moths were abundant outdoors. In fact, they flew into our house, car and everywhere else in search of a female. Now, with their cycle complete, few are observed; just the egg masses ready to hatch next spring.

Though not nearly the threat as the woolly adelgid, which is decimating hemlocks, the gypsy moth has been part of our lives for several years. According to Penn State University, nature is taking control of this destructive insect. Experts claim a fungus, commonly called Em, which originated in Japan and was first brought here in 1910, has made a significant impact on gypsy moth populations. Em’s presence is a surprise to entomologists at Penn State, for they didn’t know it had survived in quantities enough to impact the pest.

Em thrives in wet weather, such as we had this past spring. It survives the winter in soil or tree bark, then germinates in May or June. It then produces sticky spores. The caterpillars of the gypsy moth come in contact with the deadly fungus, which invades the exoskeleton and actually grows inside the body. This explains the wilted gypsy moth caterpillars around our property. They have succumbed to the fatal fungus. The fungus may also be present in the egg masses, attacking them upon hatching.

Penn State entomologists are hopeful that Em will remain a biological control for gypsy moths, but its future remains unknown. One thing is for sure; it does appear that Em has played havoc with this year’s infestation.