June 3, 2016
Plume Moths
You’ve got to be careful this time of year.
Springtime—that long-awaited, much-heralded season of color and warmth—can be positively overwhelming. The sights of brightly colored blooms and birds in breeding plumage; the sounds of mating calls and territory songs; the sweet smells of plants doing their darnedest to attract pollinators…
With your senses on overload, you may decide you need a break. Something small and plain, quiet and odorless.
You might find you need a plume moth.
These guys, members of the family Pterophoridae, are about as quiet and nondescript as they come. Often described as looking like dried grass, even their depictions are refreshingly bland.
But when you take the time to look at them, really observe their traits, you soon see they rank pretty high on the Springtime Scale of Spectacularness.
For one thing, plume moths are pretty hard to misidentify. Sure, many individuals look just like those short blades of cut grass that stick to doors and siding after a mower passes by. But once you spot one, you’ll find their primary feature is absolutely fascinating. They are shaped like the letter T.
Plume moths have slender wings, which they hold perpendicular to their body. Concealed beneath the forewings are a pair of hindwings that, typically, have fringes, and are responsible for the “plume” part of the moths’ common name.
But what’s even cooler is how the moths, to ramp up that dried vegetation-like camouflage, actually roll the edges of their lobed forewings around the fringed hindwings. With those irregular borders neatly tucked away, and their stance stock still, like dead grass, it’s no wonder the moths are so often overlooked.
BugGuide.net says that nearly 150 species of plume moth live in North America, and more than a few live here in northeastern Illinois. But, because accurate identification requires examining individuals in intimate detail—really intimate, if you know what I mean—we’ll be content today to refer to them at the family level.
Like any gathering of relatives, the Pterophoridae have some representatives that are more desirable, and some that are less. Among the latter we have the snapdragon and geranium plumes, the caterpillars of which cause damage to their namesake flowers. But among the former we have the horehound plume and the bindweed plume, which have been used to help control invasive plants.
If the showy ostentatiousness of spring has got you down, and you’re looking for a peaceful respite from the color and din, head to a porch or patio that has an (ideally night-sky friendly) outdoor light.
Plume moths are, after all, moths. Most fly at night but often end up attracted to light sources, which is where you can find them in the daytime.
At Hickory Knolls we often encounter light-colored individuals camped out on our building’s dark brown siding and door frames. In fact, just the other day I spotted a few and, yep, was completely fooled by their coloration and camouflage.
Me: “Oh, I guess the crew mowed here today.”
Me again (I was alone at the time): “Wait a minute…”
Me, once again, after closely examining the objects near the door: “That’s not dried grass! Those are plume moths!”
For quirky naturalists who talk to themselves, as well as anyone who has an appreciation for the quieter things in life, the Pterophoridae have a lot to offer. Check ’em out. You just might find they suit you…to a T…
Pam Otto is the manager of nature programs and interpretive services at the Hickory Knolls Discovery Center, a facility of the St. Charles Park District. She can be reached at 630-513-4346 or potto@stcparks.
Muted in color and quiet in habit, plume moths can be identified by the characteristic “T” posture they adopt while at rest.