The two moths that are featured today, the Walnut Sphinx and the Spotted Thyris, are pretty different from each other—one large, one small; a day flyer and a night-flyer; one from a very large family and one practically an only child; one well-biographied and the other barely known.
The Grapevine Epimenis certainly looks like a small butterfly (wingspread about an inch), and it is a daytime flyer in woodlands and edges in the eastern half of the U.S. and into Ontario. Adults nectar on the flowers of a few early-blooming fruit trees like cherries and plums and on sumac, and they like redbud. Grape Leaf Folders get their name from the habit of their caterpillars of folding grape (and Virginia creeper, redbud, and some evening primrose) leaves and webbing them shut. They can become pests in vineyards—high infestations damage leaves, which may lower production, damage fruits, and affect the next crop.
Salt Marsh Caterpillar Moths like sunny places—wet, dry, and disturbed, and can be found from the Atlantic coast all the way to Alaska and the Yukon. The SMC is a very mobile little critter, moving fast and far looking for edibles. The females lays masses of —from 400 to 1,000 at once—on host plants, and she (not surprisingly) dies a few days later. The eggs hatch in four or five days, and the caterpillars hang out and feed together during their first two instars (more than quintupling their size) before going their separate ways.
Hickory Tussock Moths are active in the daytime. They are found in deciduous woods in a range that runs diagonally across the continent from northeast to south-central—from Nova Scotia and Ontario to Texas and a bit west, nicking Wisconsin. After a male and female find each other in late spring, large masses of eggs (from 50 to several hundred) are deposited on the undersides of leaves. Often, when eggs are laid en masse, the resulting caterpillars also feed en masse. HTMs are leaf skeletonizers (they eat the green stuff in-between the leaf veins).
Pandorus Sphinxs occupy North America from south Texas to Wisconsin to Nova Scotia to south Florida. They are found at dawn and dusk along forest and river edges and vineyards where their caterpillars’ food plants grow. Adults nectar on and pollinate bouncing bet, white campion and petunias.
White-Marked Tussock Moth are in the tussock moth family Lymantriidae, a cold-tolerant lot populated by a number of black sheep including the gypsy moth. You can find them from the Great Plains to the Atlantic Ocean, including southern Canada, in mixed forests or in the shrubby edges where woods meet fields. Because of their catholic appetites, WmTM caterpillars have occasional local population booms and defoliate trees, and Christmas tree growers in the northeastern part of their range are sometimes plagued by them.
Fall Webworms are found in North America from coast to coast and border to border. They are native sons and daughters that have, since WWII, spread through Europe and Asia. Look for them in parks, forest edges, and roadsides. Cherry leaves are a favorite caterpillar food, but they will dine happily at quite a variety of trees including ash, willow, poplar, hickory, American elm, walnut, some maples, and a few fruit trees. A colony of caterpillars can eat lots of leaves, and they may defoliate part or all of a tree.
We all know the Gypsy Moth story; it’s the poster child of Invasive Species. Gypsy moths (Lymantria dispar) were imported from Europe to the Boston area in 1868 by French scientist Leopold Trouvelot. M. Trouvelot planned to do a little genetic tinkering to develop a hybrid caterpillar that was hardier than the native silkworms. Some of his breeding stock (inevitably) escaped.
The Plume Moth is a smallish moth (½” to 1 ½” wingspread) that is pretty easy to walk past, since it’s disguised as a piece of dried vegetation. All are known for their slim bizarre wings, which are deeply divided into fringed lobes. The hind wings generally have three lobes, and the forewings two, but when they are at rest, they roll the lobes of each wing together until they resemble twigs. Plume moths are found all over the world, and their flight periods include most of the warm months. The adults are often found on flowers, feeding on nectar and pollen, right out in the open.
Buck moths can be found in the Cedarburg Bog in October. Like many of their larger silk moth relatives, the adults do not feed. When they are startled, they are as likely to fold their wings and drop into the vegetation below as they are to fly away. Female buck moths lay a cuff of eggs on the twig of a larval food plant in fall, and the eggs hatch in spring. During the first half of their caterpillar-hood, the shiny, black larvae are gregarious and are picky eaters. Caterpillars pupate in early summer and the adults emerge in fall.