Roger Rittmaster stands on his back porch in Camden with a lantern he made to attract nocturnal insects. (Photo by Ethan Andrews)
Roger Rittmaster stands on his back porch in Camden with a lantern he made to attract nocturnal insects. (Photo by Ethan Andrews)
The oak trees on William Glen Drive in Camden, like many oak trees in this part of Maine, are easy to spot. They’re the ones with no leaves. More specifically, the leaves have been stripped down to their major veins by browntail moth caterpillars.

Roger Rittmaster lives about halfway to the dead-end. Bare oak trees line the road and stand naked in his neighbors’ yards. But with a few minor exceptions — a chewed crown or a buzzed limb — his oak trees look like they’re supposed to, leaves and all.

“I have to think that what I was doing had a local effect,” he said.

What he did almost a year ago was lure browntail moths to his back porch with a giant light and kill them, en masse, with a flyswatter. The jury’s still out on whether this saved his oak trees, but he’s going with it. More importantly, while the now-infamously itchy caterpillars were turning to jelly in their cocoons this spring, he was busy refining the strategy.

Browntail moths have been in New England — mostly on the coast from Massachusetts to Maine — for more than 100 years, occasionally succumbing to molds or major public health initiatives. In 2016, the population spiked in Maine, with an epicenter of sorts around Brunswick. The infestation is now solidly throughout the midcoast. The caterpillars shed microscopic hairs that can cause rashes of varying severity when they come into contact with skin. The toxic hairs get caught in the wind and settle on, or get inhaled by, people who don’t think of themselves as fraternizing with caterpillars.

After feeding on the leaves through the spring, they metamorphose into moths for July and August, at which time a second batch of caterpillars is born and runs riot until early October.

Rittmaster was already looking for moths when he stumbled on the browntails. The retired endocrinologist and Maine Master Naturalist makes a serious hobby of photographing wildlife, and a big part of his portfolio is insects that he has photographed near his home, which has a view through forest to a wide section of the Megunticook River. To attract moths and other nocturnal fliers for photos, he’s experimented with several kinds of large homemade lanterns, including a parking-lot-style sodium vapor lamp mounted in a wooden box that he designed to illuminate a bed sheet stretched between the edge of the porch deck and a row of hooks on the roof above it. He mostly doesn’t use that one, fearing that it would attract all the bugs in Camden.

The mid-size version is a basic wooden clothes-drying rack fitted with a pair of ultraviolet tubes and wrapped in a white fabric cover made by his wife. He attracted his first browntail moths with a regular porch light.

It was July 1, 2018, and there were three of them — velvety white moths with fuzzy heads, feathery brown antennae and the namesake brown abdomen visible in the cleft of its folded wings. For a photographer of moths, the appearance of a browntail wasn’t immediately more or less notable than the appearance of any other species. “I’d never seen a browntail moth before that point,” he said. “Once I went to my computer and figured out what they were, I went back and killed them.”

The next night, he brought out the drying rack and over the course of several hours killed 135 browntail moths, smacking them with a fly swatter as they clung to the fabric or tumbled onto the deck. “I don’t like to kill anything,” he said. “It was pretty brutal.”

For all that, the massacre was only a dry run for the coming season. Rittmaster coordinated with the town to shut off the streetlight on William Glen Drive, and he suggested to his neighbors that they either keep their outdoor lights off, or keep them on and try to kill as many of the moths as possible. In an idealized version of his plan, the neighborhood would be pitch black except for the glowing blue box, and in the shadows a man with an industrial vacuum cleaner.

The vacuum wasn’t his idea. Rittmaster thinks he heard of it from a reputable source — the University of Maine or the state Forest Service — but he wasn’t aware of anyone waging preemptive war against a generation of browntail moths the way he plans to this year.

As a precaution, he plans to wear a respirator and gloves — the moths don’t grow toxic hairs, but they can carry them from the cocoon, and hairs shed from caterpillars can remain toxic for years. He’s outfitted his Shop Vac with a HEPA filter and plans to fill the reservoir with soapy water in case a ride through a vacuum cleaner hose isn’t enough to startle the moths into oblivion. Using a narrow-tipped fitting for the hose, he expects to be able to suck up one moth at a time and minimize collateral damage. Even if he weren’t that careful, the alternative could be worse.

“What I’m trying to avoid is inoculating the whole tree,” he said. “Oaks are one of the best hosts we have for caterpillars, and that would kill a lot of native species.”

Rittmaster has documented 330 species of moths in his backyard. “I’d just as soon have the other 329 species stick around,” he said. As of June 25 he was waiting for the season’s first moths.