Moth Magic
There was a night-light in the room that my little sister and I shared. I was about six years old the night that a huge moth appeared in the bedroom, dark, silent wings fluttering in the corner. I wasn’t afraid, I was fascinated, captivated by the shadows it cast. I was small, but it seemed the size of my head. No idea where it came from, but it was very real. My dad has no recollection of this event. Now I believe it was a Cecropia Silkmoth, Hyalophora cecropia, which are native to the Pacific Northwest, but not common. Their larval host plants are primarily Maple, Cherry, and Birch.
Insects have always enticed me, the bigger the better. They tolerate my admiration, luring me into pursuit. Especially butterflies, but butterflies rarely sit still, so observing them is tricky. Frustrating. Brightly-colored wings dancing on flowers, tickling them with serpentine tongues. Two years ago, National Moth Week caught my attention, and I shifted my focus to the butterflies of the night. Following instructions online, I assembled a simple light trap, with a UV light and a white sheet, and at first I was surprised that they came. It was so easy! Moths come to the bulb-beacon (it is not fully understood why), and stick around long enough to get up close and personal. On summer nights as a kid in the woods, there were dozens of moths flirting with the porch light. Big Ten-striped June Beetles too. Probably a lot of other insects that I didn’t understand. But that was in the days of incandescent bulbs, beacons for insects. I had forgotten about them all.
Mostly, my moth visitors were shades and patterns of brown, cream, and black, the camouflage tones of night and daytime shadows. But occasionally someone different would appear, in a unique color, pattern, shape, or size. Early one June morning, I stumbled out of bed and checked the trap while my coffee brewed. It felt just like Christmas, and I had to blink hard and rub my eyes to be sure of what I was seeing at the trap. A Sphinx . . . Western Eyed Sphinx, Smerinthus ophthalmica. (Host plants: Willows and Cottonwood.) I trembled as I held her, took many photos, awed at her beautiful pink underwings with blue eyes. As she became agitated, her wings began to tremble, warming up after the chilly night, preparing to fly. She paused a moment at the potted purple Hyssop, full of nectar-filled blossoms. The Sphinxes are also known as Hummingbird Moths, for their habit of feeding on flower nectar during the day, hovering at the blossoms like hummingbirds.
After about two weeks of light-enticement and a collection of roughly twenty easily-differentiated species, I started keeping track of them in a notebook. This was going to be more than I could remember! Before long, I had reached forty species, and then when my daily log tallied one-hundred species, I started researching and recording the host plants of each one. While some adults don’t feed at all, and exist only to mate and lay eggs, all caterpillars need to eat. They are all Very Hungry Caterpillars (Thank you, Eric Carle), and must consume huge amounts of vegetation in a relatively short time so that they can pupate within a season.
I remember my first caterpillar encounter, a bright vignette of memory. It was fall, sometime around 1976. Dad was walking the woods, and I tagged along, kicking up the smell of damp, golden, Maple and Alder leaves. I was playing in the leaf litter, and I found a big, smooth, lemon-yellow caterpillar. It was the size of my nine-year-old finger, and even though it scared me, I held the plump, squirmy body in my hand, but dropped it when it pooped on me. It had to have been getting ready to pupate, to cocoon itself for winter. I’ve always wondered what that caterpillar became; moth or butterfly. What kind? I’ve never seen another like it.
Most moths and butterflies lay their eggs on specific host plants. Some prefer conifers, some only willows, some sedges or lichens or mosses, and others will only eat grasses. There is a moth or butterfly for every plant it seems, but some are generalists, and will dine on any vegetation. These tend to be the most widely-ranging species; very adaptable, like the White-lined Sphinx, Hyles lineata. One amazing moth at my trap is actually is a wasp parasite; the Sooty-winged Chalcoela, Chalcoela iphitalis. The females lay their eggs on Paper Wasp nests, and the tiny moth larvae chew through the paper cells and parasitize the wasp larvae, overwintering as pupae in the paper nest. A mind-blowing turnabout on the more common Ichneumon and Braconid wasps that parasitize caterpillars.
When I was 17-18, I went to school in northern New Mexico. One warm, May night during finals week, several of us second-years walked and ran barefoot along the paths between buildings. But I was struck dumb by the sight of dozens of huge, pale green moths dancing around the pathway lights. I held them, they danced delicately but frantically, long wings billowing. Luna Moths. I’ve never seen them since. They exist east of the Rockies, ranging to the western Great Plains, and apparently Las Vegas, New Mexico is the western extent of their range.
When the chilly nights of fall arrived, the moths mostly disappeared from my light for the season. In reality, they were still there, but in a different form. Most moth young pupate (cocoon… the moth equivalent of a chrysalis) in the fall, waiting in leaf litter or tucked into cozy crevices like tree bark until spring. This is why it is important NOT to rake up and dispose of leaves in the fall. Some species diapause as nearly-mature caterpillars, just shy of adulthood. They wait in a kind of chilly suspended animation in vegetation or soil, waking on warm days to feed and going back into torpor when cold and rain return. By October, I had logged a surprising 143 species of moths on my back porch. I identified them to the best of my ability, with the help of the moth community. And yes, that is a thing. I call them the Moth People.
Winter was dark and moth-less. But February arrived, and I saw the glitter of a moth in my headlights one night. I set up my moth traps again straight away and waited. I was excited to see how many I would find by starting earlier in the season. The 2023 Moth Season started slow with the cold, wet days of spring but increased exponentially in mid-May with the explosion of vegetation and warmth. I started anew with my species and host plant count, but with a simple database that allowed for better cataloging. What astounded me is that while about 75% of them I recognized from the summer before, there were so many new ones! Tiny, micro-moths and larger sphinxes. I had multiple visits from three different sphinx species over the summer of 2023. Tiny yellow-and-black Gold-base Tubic (Oecophora bractella, host food: decaying wood), pretty Small Magpie (Anania hortulata, host plants: Stinging Nettle and other members of the Mint family), patterned black on white, and so many more. I did my best to identify each, and learned their larval host plants. T-shaped Artichoke Plume Moths (Platyptilia carduidactyla, host plants: Sunflower family plants), and the incredible wasp-mimic, the Raspberry Crown Borer (Pennisetia marginata, host plants: Blackberries and Raspberries). The light green Pale Beauty (Campaea perlata, host plants: many deciduous and coniferous plants), golden October Thorn (Tetracis jubararia, host plants: Alder, Birch, Poplar, Dogwood), and glorious new thing to me, the Great Tiger Moth (Arctic caja, host plants: Mint family, Blackberry family, Poplar, and others), outerwings patterned black and white, underwings bright orange with electric blue spots, and fuzzy brown body. They were all so incredible!
Last week, I dreamed that I was roadtripping, driving shortly before sunset. I drove as the orange, setting sun bathed rounded, granite boulders. The breeze warm through my open window. As I drove through the open range, near the scrubby vegetation, I spotted a huge, orange-red caterpillar, lined with eye spots, horn on its tail. I quickly pulled off the road so I could investigate, as you do. It was a Pandora Sphinx . . . we don’t have them here, they’re found in the east. It was beautiful, and I picked it up and admired it before putting it back on a shrub, out of reach of the nosy, black cows nearby. I’ve never seen one in the flesh. Yet.
I have always understood that insects were important to ecosystems and, thus, important to us all. But my little moth project demonstrated to me just HOW important. This became my soapbox: a diversity of insect species is dependent on a diversity of plant and lichen species. A diversity of songbird species is dependent on a diversity of insects, because nearly every songbird feeds their offspring insects, especially the plump and juicy caterpillar children of moths and butterflies. Watch warblers hop around leafy branches, hunting for them. Bushtits and Sparrows too. And adult Hummingbirds actually feed on insects themselves, as well as feeding them to their chicks. Animal protein is vital to reproduction. There are caterpillars everywhere, in all colors, sizes, and bristliness, with horns or no. Inchworms. Cutworms. Hornworms. Many are considered agricultural pests, but in a diverse ecosystem, they are not pests at all. They are are keystone lifeforms.
The more moth species, the richer and more resilient the habitat. Moths matter.
Early this August, I finally witnessed a Hummingbird Moth feeding in my cutflower garden. After purposefully planting many kinds of night-blooming, perfumed, moth-shaped flowers on my porch, in the end it was dark blue Larkspur. There she was, a White-lined Sphinx sipping nectar in the blue Delphiniums. Next year: Delphinium species everywhere!
I love this, and especially that you include host plants (a revelation to me!). I'm looking forward to more of your writing.
Thank you!