By: Jessica Blessing-Patterson
Fall is undoubtedly the most glorious time of year here in Saint Louis. With the early evenings and cool breezes we get a much needed break from the brutal summer heat. Missouri also has an exceptionally diverse population of deciduous trees and shrubs, which put on a spectacular show as they change colors. They create a seasonal spectacle that rivals any perennial flowerbed. However, once the show is over and all those luscious leaves fall to the ground we gardeners tend to rush out for the big fall clean up. Here in U City we even have leaf pick up provided by the city to facilitate the process. All that is well and good for keeping a lush lawn and clean gutters but what would happen if we skipped that part? What would happen if we chose a little piece of garden to leave alone and not “clean up?” The answer to that question might come in the form of a beautiful surprise visitor.
Here in the Show-Me-State we have a diverse population of Lepidoptera. “What’s that crazy word mean?” you might be thinking. Simply put, it’s how we classify Butterflies, Moths and Skippers. These insects are extremely prevalent not only in our environment but in our culture. The huge push to save the Monarch has been felt nation wide, not just here in Missouri. The Monarch though is the only migratory butterfly we have so what do all the others do in the winter? They keep a low profile that’s for sure, seeking refuge in the soil, under bark, inside stems and yep, right there in that pesky leaf litter. Here is a little info about 3 of my favorites who all happen to be in the same family: The Giant Silk Moths.
The life cycle of the Luna Moth is only about 2months unless it is the generation that pupates in the fall. In this case the pupa with overwinter in the fallen leaves of it’s host plant. Luna moths seems to prefer a variety of leaves depending on the region they’re found in which can include: Birch, Alder, Persimmon, Sweetgum, Hickory, Walnut, Sumac, Moonflower, Sycamore, Hornbeam, Hop Hornbeam, Elm, Willow and Ash. Chances are pretty good you’ve got once of these species in your yard or on your street, which is why this moth is considered common even though they’re rarely seen. The reason for its rare sightings are that it is not only nocturnal, it also only lives in it’s impressive adult stage for about a week. It emerges from is chilly winter home as a spectacular mint green stunner who actually lacks a mouth entirely. They will immediately find a mate, lay their eggs and soon perish.
The life cycle of the Polyphemus Moth is not so different from the Luna. They too feast on a similar diverse pallet and will overwinter in a cocoon, however rather than wrapping a leaf around their cocoon, the Polyphemus moth will attach their cocoon to a twig or branch of their chosen host plant. This makes them a little less susceptible to being chopped up by the leaf grinder or lawn mower unless of course they’ve cemented themselves to the crab apple out back you’ve been meaning to prune for years… The adults like the Luna will emerge with no mouth and a one-track mind. Where they differ from the Luna is their color. Generally, they are a dark tan color with distinctive “eye spots” on their fore and back wings. At the center of these spots the wings are clear and lacking the overlapping scales that give the rest of the wing their beautiful dun color.
Last but not least of my favorites is the Cecropia Moth. This is the largest native moth in North America with a wingspan of 6 inches for the adult females. They too will over winter as a pupa making them very susceptible to being chopped in the chipper. They lash themselves to their host plant, which can be Maple, Willow, Plum, or Lilac. The Cecropia is extremely attracted to light in the evening hours and can be spotted if your lucky by porch or street lights April through June. They differ in color from the Luna and Polyphemus moths, and have a characteristic crescent moon shape in white on their wings. Their bodies are very fuzzy with bands of white and red.
In closing, these species of Lepidoptera are perfect jewels of the natural world. Their spectacular colors and unique life cycle can dazzle and delight even the most resistant urban dweller. The only thing we need to do to give them a habitat and a little bit of a break is nothing. Leave a place in your yard where the leaves stay cold and damp. Keep the dead looking stems for a while, what are they really hurting? If it really bothers you, pick a place in the yard you don’t get to regularly. Clean out these spaces every other year so populations have time to reestablish. Use native plants and know that your lack of enthusiasm in fall clean up probably saved a life, albeit a very tiny one.
Recommended reading: Insects in winter by Dr. Douglas Tallamy