Why these Mainers must pick between a chemical pesticide and a natural poison

Microscopic hairs on the browntail moth caterpillars can cause “a blistery, oozy rash and respiratory distress,” according to the Maine Forest Service. (Photo courtesy of Maine Forest Service)

Microscopic hairs on the browntail moth caterpillars can cause “a blistery, oozy rash and respiratory distress,” according to the Maine Forest Service. (Photo courtesy of Maine Forest Service)

With the Back-to-the-Land ethos still prevalent in environmentally friendly Maine, the idea of signing a paper letting the government spray pesticides over your property has got to be cringe-worthy for some.

But the alternative — allowing invasive browntail moths to spread, devour the spring foliage and potentially blanket the area with toxic hairs — would be worse, Cumberland Town Manager William Shane suggests.

The Town Council is holding a workshop on its pesticide plan tonight at Cumberland Town Hall, where a representative of Whitney Tree Service, toxicologist Lebelle Hicks and Charlene Donahue of the Maine Forest Service Insect and Disease Laboratory will share their thoughts about this conundrum.

The plan is this: Have professionals take a specially equipped truck down Route 88 spraying the chemical pesticide known as Tempo on the trees along both sides of the road. Residents in the affected areas are being asked to sign a paper that either consents or refuses consent for the treatment.

Route 88 approximately follows the coast, but is far enough back that it largely avoids the ecologically sensitive no-spray zone along the waterfront.

Courtesy town of Cumberland

Courtesy town of Cumberland

The idea is to keep the creatures from making their way farther inland, and time is of the essence. If the leaves on the trees aren’t treated with pesticides before the browntail moth caterpillars emerge from their cocoons and start eating — which is expected to happen within the next month or so — it’ll be too late.

My colleague, Bangor Daily News outdoors writer Aislinn Sarnacki, knows a thing or two about these buggers, and she wrote a piece last year about the problems they create for people. As Aislinn wrote:

“Direct contact with a caterpillar isn’t necessary for ill effects. When the caterpillar molts, the barbed hairs break-off and become airborne. These airborne hairs can lodge into people’s skin or be inhaled, and the hairs remain toxic for a year or more after they break away from the insect.”

On the skin, they can cause a reaction similar to poison ivy, she wrote, while in the lungs, they can cause severe respiratory problems.

Cumberland Town Manager Shane might have a harder sell on his hands if not for the fact that many in the area remember a particularly nasty infestation of the caterpillars around the turn of the last century.

“They cause itching and respiratory issues and many of our residents in the late 1990s to early 2000s suffered greatly because of these critters,” he wrote in a memo last week to town councilors, adding that he was “getting very positive feedback” on the spraying plan, perhaps in part because nobody wants to go through that again.

Charlene Donahue, who is slated to be one of the experts on hand at Cumberland Town Hall tonight, told Aislinn there are few reliable natural ways to control these creatures, which were introduced to Massachusetts from Europe at the end of the 19th century.

They spread across much of the northeast over the next decade and half, according to the Maine Forest Service, but then populations mysteriously dropped off, with some isolated pockets surviving on Cape Code and a few Maine islands.

The lack of real understanding about why browntail moth populations occasionally explode and then recede is one of the more frustrating things about them.

Shane wrote that when the moths were taking off in the Cumberland area 15 years ago, the town was saved by an unexpected tree mold outbreak that, luck would have it, came around at the right time to crater the browntail numbers.

Now, he wants to be more proactive.

The scary part? On the state’s browntail moth risk map, Cumberland’s actually only in the “moderate” threat zone. The “high risk” towns are a little further north, with the coastal corridor stretching from Freeport and Harpswell up through Woolwich and Bowdoinham expected to bear the brunt of this year’s caterpillars.

Browntail Moth Risk Map

Seth Koenig

About Seth Koenig

Seth has nearly a decade of professional journalism experience and writes about the greater Portland region.