The teacher came over one night and showed Duke how to set up the trap. The ultraviolet light draws in the insects, which fly around and around it, eventually bonking into a metal fin that momentarily stuns them, and then they drop into a hole where they are trapped and killed by poison. “The training was important, because back then we used calcium cyanide,” Duke says. He laughs quietly, recalling those simpler days when people let 7th-graders handle chemicals that could kill the neighborhood. They set up on a spot where Duke had a hay-bale fort when he was younger. He found the continuity pleasing—still his play area.
Until that night with the teacher, Duke had only collected bugs at porch lights or with flashlights in the garden. But this was the real deal. He ran a power cord from the garage out to the black light and then stood in the kitchen window to watch the action. “It sure got off to a great start—I had many hundreds of beetles and moths in a night’s trapping, including some big, showy ones,” he says. Duke crooks a smile, the images rolling through his mind. “It was really exciting all the time.”
Also stoking Duke’s obsession was the bug-friendly geography near his childhood home. Stevensville, in the southwest corner of the state, is a great crossroads of bug traffic. He caught insects that had blown in from the Great Plains, bugs that had migrated from the East Coast. Occasionally a storm system from the Gulf of Mexico would sweep in bugs from Louisiana, and the North winds ushered creatures down from Canada. Even Stevensville itself, a particularly hot and humid part of Michigan, gave rise to hordes of insects. “Sometimes I’d have to wear a dust mask to keep from breathing so many bugs in,” Duke says.
Each day, the young Duke would pick through the night’s haul, select a few of the best specimens for his own collection and then box up the rest and ship them to the ag-extension headquarters at Michigan State University. There, staff entomologists would sort and count the insects. Eventually he visited MSU, and the staff quickly saw that the boy could be trusted to ID and count the bugs himself, so they saved the postage. “I was a fanatic, and when you are a fanatic, you can learn anything,” he says. When Duke later attended MSU, he became one of the bug sorters. Duke has many fond insect memories from his MSU days, but one of his favorites had nothing to do with class work. Once in a while, at night, Duke would drive his convertible down to the vast greenhouses on campus, acres of luminescent glass buildings that would attract millions of insects. There he would sit, top down, enjoying the drama as a cloud of insects gathered above the glow, and hundreds of bats swooped through the swarm, feasting on the winged multitude. Duke doesn’t ever recall taking a date on the outing, “but that is the sort of stupid thing I would have done,” he says.
In the twilight of an August evening, Duke stands rigging an ultraviolet trap in a forest above the Boardman River Valley, near Brown Bridge Pond. Tonight he is offering a guided bug tour to anybody who cares to show up. He gives the walks periodically throughout the spring and summer, announcing them on the radio. At the last one, just one couple and their 11-year-old daughter attended. But the low turnout didn’t faze Duke—any chance to share bug wonder is a good time for him.
Duke’s favorite bugs are moths and butterflies, and August is the peak time for hunting one of Michigan’s moth beauties, the underwing. “It makes August worthwhile,” he says, jazzed about the evening ahead. The state has about 1,000 moth species, many so similar that even Duke can’t identify them all.
Tonight Duke will use two lures to bring in the bugs. One is his ultraviolet light, which is effective but limited because not all moths are drawn to light. The other lure is a fermenting goo of brown sugar, beer, bananas and plums that Duke spreads on trees with a paintbrush. He found the recipe, named “Sugaring for Moths” in what he calls “the first great North American moth book.” It was published in the 1890s and was titled simply, The Moth Book.
Next to his ultraviolet light Duke hangs a white sheet where bugs can land, and folks can study them. Then, as the last light eases from the sky, Duke picks up his partially filled 5-gallon bucket of goo, puts a clear plastic glove on, grabs his paintbrush, and heads down a path. He swabs goo on an oak, a jack pine, another oak, dead trees, live trees, one tree after another. “Many critters will feed on this—millipedes, ants, daddy longlegs,” he says. “But the one we are after is the underwing.”
Underwing moths belong to the largest family of moths in Michigan, and the species hunted tonight are the largest of the family, but still, they’re not that large—a little bigger than a silver dollar. Underwings are common, but since they don’t come to lights, most people never see them. Our evening is shaping up well for underwing attracting. The forest stays warm, the air humid and still. In Duke’s wake, the fumes of fermenting fruit goo linger along the path.
He heads back to the trailhead, and by now about a dozen people have arrived—a mix of old and young, with families and alone. Night has fallen and the orange orb of a full August moon rises through the trees. The bug crew is ready, and the warbling call of a loon adds the perfect nature-show touch. Duke says it’s time to check the baits. He leads the way, a half-dozen flashlights sweeping the forest floor behind him.
Duke stops at an oak and finds nothing. At a red pine just a daddy longlegs. Then, at an oak with a carpenter ant nest, he reveals a frenzy. Half-inch-long black ants, each with a stripe across the abdomen, swarm over the goo. “They were asleep for the night, but I put the lure on and they were sent out to lick it off,” Duke says. Another lure has attracted a beetle. “He usually eats caterpillars, but he’s just having a great time with his head in the slime, soaking it up.” Finally, Duke finds an underwing, but the children rush it in their excitement, and it flies. Every flashlight tracks its flight into the trees. As it leaves, it shows the flash of color under its wing that lends the species its name.
Eventually an underwing lands right where everyone can see it, on Duke’s belly, though he never put the fruit mixture there. Again, all the flashlights zoom in. But this time the moth performs on cue. It opens its brown camouflaged wings and reveals a brilliant orange pattern, shaped like two owl eyes that entomologists feel is a trait evolved to scare away birds. Soon, the moth begins to vibrate. “He’s warming his muscles so he can take off,” Duke says. And then the moth is gone. As the night wears on, Duke and the crew find several more underwings, every one a wonder. The camouflage so perfect you can barely make one out even though it’s just a few feet away. The colors underneath are breathtaking. It’s the kind of life form that can convince anyone that God exists.
Duke enjoys moth walks and bug hikes, but he never forgets that his job is first and foremost Agriculture Extension Agent, and if anybody ever doubts that, all they have to do is read the front of the hat he wears every day, which reads, “National Association of County Agricultural Agents.” He wears the hat one summer afternoon as he roams the trails at the Grand Traverse Commons, bug net in hand.
His farming perspective explains why, when asked about the area’s most dangerous bug, he names something that presents no harm to humans. “The cherry fruit fly, at least from an economic-damage standpoint.” The insect is found as a maggot in cherries, and there is a zero tolerance for it at the processor. “If one grub is found in a truckload of cherries, the entire load is rejected,” he says. “The marketplace is very demanding— no bugs, no pits,” he says.
One of Duke’s roles is to help figure out the most strategic time to spray pesticides to prevent the cherry fruit fly. Now farmers know how to set traps for the insect, allowing them to react as early as possible and ultimately use less pesticide. “The plum curculio is another one,” he says. “But that one is more tricky, and there’s a major effort to get it sorted out.”
Since 1990, Duke has also been a voice of MSU extension in the Grand Traverse region, doing a weekly radio update, information to help the farmers he was concerned about even as a boy. “I remember listening to the agriculture agent on the radio at my uncle’s farm,” he says. “I never imagined that one day I’d be that guy.”
As he walks, Duke occasionally interrupts his ag-extension schpiel to talk about a bug he sees. He turns over a leaf with an insect slaughter going on underneath: aphids being feasted on by mites and beetles. He spots something that looks like a bird turd and explains that it’s actually a swallowtail larvae. “It’s a different kind of camouflage,” he says. “It’s not trying to look like the background, it’s trying to look like something you don’t want to eat.”
The thick growth along the trail opens briefly and there are two guys in their mid 20s, sitting at the edge of Kid’s Creek, sharing a bottle in a bag. They eye Duke’s bug net, and one says, “you on a bug hunt?”
For over 30 years the staff at Traverse Magazine has written about the history and natural world of our region. For the web series, Traverse Classics, we've reached into our archives to bring our favorites to our MyNorth.com audience.