What Is This Moth?

Jeanene Davis of Crescent, IA, asks: “We found this moth on one of our bushes and haven’t been able to identify it from any of our books. What is it?” Here’s the answer.

This large and colorful moth is the Imperial moth (Eacles imperalis). It’s in the silk moth family (Saturniidae), which also includes the Cecropia moth and the Polyphemus moth. They have a wingspan from 3 to 6 inches, with the females being larger than the male.

They’re most active in spring and summer, and range from Texas north to Nebraska, then east through Iowa, Illinois and the eastern U.S., from Florida to Vermont.

Though their range is extensive, they’re not that common, so seeing one is a real thrill. Their host food plants are deciduous trees—including honey locust, maple, oak, basswood, elm, birch and walnut—but they’re not considered garden pests.

One amazing fact about all the members of the Saturniidae family: As adults, they have no mouthparts, which means they eat only when in their caterpillar stage of life.

Bill Johnson is a Minneapolis-based nature photographer.