Milkweed tussock moth
Euchaetes egle
The tufted caterpillars that turn up in a crowd in late summer and strip a leaf to its veins in a day.
What it does on milkweed
The moth lays eggs in a mass, and the young caterpillars feed together, skeletonizing whole leaves before dispersing as they grow. They accept older, tougher foliage that a monarch larva would refuse, so they mostly appear after the monarchs have finished. Adults are among the moths that answer a hunting bat with a burst of ultrasonic clicks, which the bat has learned means an unpalatable meal.
How to recognize it
Caterpillars are unmistakable: dense tufts of orange, black and white hair. Early instars are pale gray and hairy and feed in a mass. The adult moth is plain mouse-gray with a yellow-orange abdomen spotted in black.
Where and when
Eastern and central North America, west to the Great Plains. Most often seen July to September.
Should you do anything about it?
Leave them. Late-summer defoliation costs an established plant nothing, and the roots carry it to next spring. Move them to another stem only if a container plant is being stripped.
Milkweed tussock moth: common questions
Do milkweed tussock moth caterpillars eat monarch caterpillars?
No. They compete for the same leaves but do not attack larvae. They also feed later in the season, when most monarch caterpillars have already pupated.
Are they safe to handle?
The hairs can irritate sensitive skin. There is no venom, but move them with a leaf rather than bare fingers.
Cite this page
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Milkweed USA. (2026). Milkweed tussock moth (Euchaetes egle). Retrieved DATE, from https://milkweedusa.com/wildlife/milkweed-tussock-moth/
"Milkweed tussock moth (Euchaetes egle)." Milkweed USA, 2026, https://milkweedusa.com/wildlife/milkweed-tussock-moth/. Accessed DATE.
Milkweed USA. "Milkweed tussock moth (Euchaetes egle)." Last modified 2026-08-01. Accessed DATE. https://milkweedusa.com/wildlife/milkweed-tussock-moth/.
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title = {Milkweed tussock moth (Euchaetes egle)},
author = {{Milkweed USA}},
year = {2026},
url = {https://milkweedusa.com/wildlife/milkweed-tussock-moth/},
note = {Accessed DATE}
}