Photo supplied.
Gypsy Moth damage
Well, as much as I hate to admit it, I realize I really am a glass-half-empty kind of guy. The lack of rain and the devastation being caused by the gypsy moth caterpillars are only bringing home to me this depressing fact more and more clearly.
Lisa Stefaniak’s wonderful column last month (A Village Tree, June 2021) dealt with the majestic oak at the end of Prince Street, and how it’s beautifully viewed from a bench at the water’s edge on Lower Medd’s Mountain Trail. Sadly this glorious tree (and another very near it) now has hardly a leaf left. And the culprit: the caterpillars of the European Gypsy Moth. If you’re one of the lucky people who have not yet seen these creatures, let me tell you about them.
Way back in 1869 a Frenchman by the name of Trouvelot imported this species of moth to Massachusetts with the idea of cross-breeding it with the silk moth in order to create a silkworm industry in the USA. Trouvelot was an artist, an astronomer and an amateur entomologist; what he wasn’t was careful and tragically this foreign species escaped and, with no native predators, rapidly spread far and wide. This summer, and the worst in many years, we are once again seeing the disastrous effects.
Luckily the gypsy moth has only one generation a year. The innumerable caterpillars destroying the tree canopy will be descending soon and pupating on the bark of the tree trunks or in clusters of leaves. Later the adult moths will emerge and mate, then the females will lay casings each containing hundreds of eggs on the bark of trees. These eggs will remain through winter and next year a new generation will emerge. We can only hope that a cold winter (last year’s wasn’t cold enough) will kill the eggs.
In Lisa’s column last month, she noted how important oak trees are as a source of caterpillars, which are an important source of food for many animals, including birds. Lisa, however, was not talking about this introduced species of caterpillar, and unfortunately our native birds have not really developed a taste for these bristly creatures. Anyone walking along a sidewalk under trees will have noticed a strange debris rather like pepper. This is the frass or excrement of the caterpillars. If it’s quiet enough you can actually hear it falling!
So much for the bad. Now how about something good? Another introduced species is nesting on my front porch this year. Robins had built a nest as usual; things were going well, and then all of a sudden the nest was deserted. I expect a squirrel or crow or Blue Jay robbed the nest of its eggs or nestlings. The nest sat empty until last week when I saw a tiny head and beak peering over the edge. A pair of House Finches has taken up residence. This species is native to the western United States and Mexico; but someone in the years between the two World Wars thought they could make a profit by selling them as cage birds. It seems sales were not good, so these poor caged birds were released in 1940 on Long Island, New York. Those freed birds found the East to their liking and bred, and the subsequent generations have spread throughout the eastern US and southern Canada.
Unlike the gypsy moth, House Finches don’t seem to have become a problem. Both male and female are typical finches, buff with darker streaks, and the male plumage is handsomely enhanced with raspberry. On my porch the male comes and feeds the female and sings his melodious song to her.
We take the good with the bad. Our weather has been far from generous: late frosts and insufficient rain have kept gardeners, farmers and orchardists up at nights. The plague-like attack of caterpillars has caused the authorities to spray the Ganaraska Forest, while closer to home we all shake our heads and hope for the best. Nature is always unpredictable; and many of the things we have done have created simply more problems and caused it to be even more unpredictable. No, the subject of climate change must wait for another day–my glass is already half-empty! But the introduced finches on my front porch know nothing of this. They are the lucky ones. Get out! And enjoy!
GET OUT! by Glen Spurrell
