Douglas-fir tussock-moth caterpillar

FUZZY MENACE — West Volusians are no doubt familiar with the Douglas-fir tussock-moth caterpillar, pictured here. While annoying, the caterpillars are largely harmless, and once they become nondescript brown moths, the insects will largely go unnoticed. They can still cause irritation. “The d*** things ate my blueberries,” Beacon publisher Barb Shepherd candidly told this reporter.

Surely you noticed the fuzzy caterpillars. Though diminished in number now, their invasion of West Volusia has been hard to miss.

The nuisance in question is the Douglas-fir tussock-moth caterpillar.

They’re about an inch long with small red heads and bodies covered with pointy hairs. These creepy-crawlies are venomous, but not particularly dangerous. For some, the worst reaction to their bristles is a rash.

“Some species, like these moths, cacti and porcupines, have defensive hairs or spines that can penetrate the skin and are irritating to some,” Dr. Terence Farrell told The Beacon

Farrell is a professor of biology at Stetson University in DeLand.

While the caterpillars have dangled from trees, infested some bushes and covered flat surfaces for weeks, Farrell said they are on the way out.

“The caterpillars are already mostly in their cocoons,” he said. “When they hatch out early next spring, you won’t notice them. It Is only when they eat a bunch of leaves and get large, then drop to the ground to start looking for good places to pupate that they become so obvious.”

Caterpillars begin pupating when they build themselves into a chrysalis or a cocoon, prepping for their transformation into a butterfly or moth. The tussock-moth caterpillars build silky-looking cocoons on trees and other surfaces. After 10 to 14 days, they emerge as moths. 

“The adult female moth never really leaves the cocoon — she doesn’t have functional wings,” Farrell said. “The male flies to her and, after sex, she pulls back into the cocoon and lays her eggs there.” 

Next spring, when the eggs hatch again, the life cycle continues, and West Volusians will once again be terrorized by this fuzzy menace.

As for dealing with them, DeLand Garden Club Grounds Chair Norma Thomas argued that, while annoying, the caterpillars are a short-term nuisance.

“They’re just not a problem down the road,” she said. “They’re not even on my radar in a couple of months. They’re on my radar now because they’re walking on my legs.”

Douglas-Fir tussock-moth cocoons

TIME TO TRANSFORM — When Douglas-fir tussock moths pupate and begin their two-week transformation into moths, they spin silky cocoons like those pictured here, often on trees or the eaves of houses. DeLand Garden Club Grounds Chair Norma Thomas said not to worry, though. If homeowners get to the cocoons early enough, they can be knocked down with a broom. After that, well, most people have to pressure-wash their eaves yearly, anyway.

If you want to smash a bug, Thomas said, direct your ire toward the Eastern lubber grasshopper, which is larger and much more likely to damage your garden.

Gardeners desperate to eliminate the fuzzy scourge can use a bacillus thuringiensis, or BT, insect-killer. This type of repellent is not particularly invasive, Thomas explained, and targets only insects. 

With the caterpillars on the way out, Thomas recommended just leaving them be, and brushing them off of surfaces and plants if they become too much of an issue.

“We’re not in control of everything,” she said. “Every creature has to have some defense. Their sheer numbers are their defense.”