During the first Rombout Middle School track meet of the season, people were walking into spider webs just like in the Gwen Stefani No Doubt song. Even while on snack pickups at the grocery store, spider webs were flying. Countless webs were glimmering as they floated across Hammond Track in the setting sun, with bugs flying in between them. Soon, the curiosity turned to annoyance as little black caterpillars were walking across shirts, arms and legs everywhere. They could not be brushed off quickly enough.

The next day, Beacon City School Superintendent Matthew Landahl sent an email update to district families, saying that these flying caterpillars were spongy moths, which have been causing rashes if come into contact. He provided reassurance on what the school was doing to deal with them: “We value our students having time outside and our facilities team will clear our playground equipment before recess daily so our students can access our playground equipment. Our building principals will monitor playgrounds and they may decide to implement indoor recess if there are too many present on our equipment.” He did not not anticipate an impact to extracurricular activities.

And so begins the season of the gypsy moth, according to Cornell College of Agriculture and Life Sciences (CALS). The allergic reaction comes from the hairs of the caterpillar, according to Cornell: “The tiny hairs (setae) of spongy moth caterpillars carry histamines that can cause an itchy, red rash in some individuals.”

The caterpillars begin in an egg mass laid by gypsie moths in July/August. The mass is stuck on a tree, and if it survives the winter, 100-600 eggs will hatch as larvae. They grow into caterpillars, and leave the mass, often on a single silk thread that is carried by the wind until it lands on a surface that the caterpillar likes and can feed from. According to Cornell: “Early instar larvae are small, dark brown-to-black, and very fuzzy. Later instars lighten in color and have a showy display of two rows of colored spots: five pairs of blue and six pairs of red.”

Then in June/July, “larvae pupate in hiding spots under bark or similar protection,” explains Cornell. They are about 2” and dangle. “Once they complete pupation, adult male spongy moths emerge and fly erratically during the daytime in search of mates. Heavy-bodied adult females have wings but don’t fly. They rest on trees and wait as males follow female pheromone trails to find them.”

White footed mice and fungus are the killers of the caterpillars, according to this report by the Highlands Current. And a stress-induced virus. “Eventually, the caterpillar population will get so big that it will get stressed trying to find enough food, weakening their immune system and making them more susceptible to a virus that is always present in the population, but sub-lethal when stress levels are low.”