Prepare for an unwanted reminder that spring has arrived – the return of the cankerworm.
In scattered locations across the Charlotte area, the hatching of these foliage-eating worms will send many people to hardware and home supplies stores to fight a battle that arborists say should have been fought last November and December.
Over the next two weeks, the worms will hatch from eggs and begin munching on newly emerged leaves. Some of the worms will glide on silk threads to the ground, where they will begin their assault anew next winter.
The worms are predictable, usually hatching around Easter, Charlotte city arborist Don McSween said.
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In addition to eating tree foliage, the cankerworms also leave droppings on the ground. For years, the problem was confined to parts of Charlotte and scattered locations in the outlying areas. Last year, the worms had a big impact in Matthews and southeast Charlotte. The worms prefer willow oaks, but they’ll eat the foliage from about 50 other types of plants and trees.
The real way to fight the worms is to put bands and a sticky material around tree trunks in November, before the worms begin crawling up the trees to lay eggs. But when the cankerworms start hatching in the spring, arborists hear from people who never got around to banding their trees.
“We had people come in today and ask for the banding material,” a sales clerk at Monroe Hardware in Mint Hill said Tuesday afternoon. At this point, however, it’s too late.
The best bet now, McSween said, is to use some sort of insecticide against the hatched worms.
“Be sure to read the label carefully,” he said.
Frank Cegielski, a tree specialist with Monroe Hardware, says the best approach is either to use a systemic pesticide or an organic compound called bacillus thuringiensis, or BT.
“Use the systemic pesticide as soon as possible,” he said. It is applied to the ground around the tree, and the tree absorbs it. “It gets into the leaves, the worms eat the leaves, and they die,” he said.
BT, meanwhile, is a bacterial compound that the worms eat – and then die.
In years past, the City of Charlotte paid for planes to spray chemicals. But the worm problem is much less acute in recent years for such an expensive operation, McSween said.
“They’ll be gone in a few weeks,” he offered as consolation.