LAKE GEORGE, NY (NEWS10) – Over the past two months, anyone surrounded by plenty of trees in the North Country may have heard a telltale chorus similar to falling rain – even when the sky is clear and blue. Now, at least in parts of the North Country, the telltale melody of the gypsy caterpillar has died down.
On Tuesday, Warren County Soil and Water District Manager Jim Lieberum said he had seen a drop in the invasive moth, which last year stripped trees bare across much of it. of the Lake George region. This year, he saw them reappear, with a month of May with less water than is ideal for controlling the insect population. Lieberum, who lives in Thurman, first noticed a change in her own backyard.
“I noticed that the caterpillars were just on the trees. They weren’t moving, they were kind of huddled together,’ he said. “I kept an eye on them and assumed they were sick. They fell afterwards and, as in some parts of the county, they were wiped out.
The squishy month — whose name was changed to squishy after last year’s boom — lays its eggs at the base of trees, near the ground. In the spring with sufficient rainfall, water penetrating the soil stirs up pathogens that wipe out larval populations before they ever have a chance to hatch, keeping total insect numbers down. a low level. In 2021, not enough rain fell to kill the usual portion of caterpillars that never make it to the moth.
Since mid-May, 2022 has started to look more optimistic. The clumped caterpillars found by Lieberum were coated in a white substance – a sign that a virus was making its way through the population. As caterpillars, spongy moths climb trees and feed on pine leaves and needles, in quantities that can prove deadly to trees if left unchecked. Arrested caterpillars, clustered and motionless, are a sign that recent rains have given these pathogens the boost they need, preventing these caterpillars from pupating, becoming moths and continuing to spread eggs. .
However, not all parts of Warren County are free of sponges. Fully pupated moths have been spotted flying around in Crandall Park in Glens Falls, another area that has seen plenty of moths chewing leaves in 2021. Places that have seen death have just seen it at time, county staff finding many of the caterpillars are thriving and growing in places where the rain hasn’t taken effect quickly enough. Even in places where caterpillars survive in time to pupate, more rainfall could still reverse the trend.
“Last year, some (caterpillars) on my property started pupating,” Lieberum recalls. “I felled a tree – a small pine tree that was dead – and the top broke off. There were probably 20 or 30 cocoons in there, and I crushed one – disgusting smell – and so the virus must have killed them while they were in there.
Even though the spongy moth has been stopped in its tracks for now, the impact on the Adirondacks is visible. Areas of trees left bare and leafless can be seen around Lake George, Queensbury and south to Saratoga Springs.
Hardwood trees will regrow – they can withstand a buffet of spongy moths for a few years before their lifespan is threatened. It’s a different case entirely for pines, which the caterpillars can chew through much faster and can’t regrow their needles as easily. This means that even though the gypsy moth boom only lasted May and June, pines on private properties and in parts of the Adirondacks could reach an early end of life. The degree of danger posed by death can be difficult to predict.
“Trees can stand forever or fall at any time,” Lieberum said. “You can’t tell what’s going on in the tree, in the soil, and in the root system.”
Any homeowner with a dead pine that is in danger of falling on a house should have a professional deal with it. If the tree is in a backyard or in acres of wooded property, the felled tree is not an immediate danger, but rather a change to the local ecology that needs to be addressed. A few years later, there may be more greenery on the ground around where the tree fell, and other types of trees will grow in their place.
Lieberum says that a number of gypsy moths appear each year – if soil-bound pathogens could eradicate them completely, there would be no problem. Populations can explode, but can only travel to adult female moths, which are flightless, and therefore lock in population growth to a certain rate. Even so, there are times when butterflies can expand their territory without a clear rhyme or reason.
“If you come to Warrensburg, probably other places, it’s like, ‘This oak tree got hit, but this one didn’t.’ In other places they will be really focused on the oaks, so the maples are fine.
Those who still keep an eye out for gypsy moth caterpillars should know what steps they can take. Now that the egg clusters have hatched, double-sided tape similar to fly paper is a popular method. Wrapping it around tree trunks can prevent caterpillars from entering branches. When all else fails, experts say there’s nothing wrong with getting out and picking invasive plants from branches by hand.