One of the last things you expect to see on top of snow is a caterpillar, but it can happen. Certain species can withstand the cold of northern New England winters and remain active throughout the colder months. Among them is the “Winter Cutworm,” or larval stage of the Large Yellow Underwing Moth (Noctua pronuba), a relatively common Noctuid (a family of moths that typically has dull forewings and pale or colorful hind wings).
These larvae actively feed on the roots and foliage of plants (grasses, weedy plants and a variety of garden vegetables) through the winter, and on warm days can appear on top of the snow. They pupate and emerge as adults in spring and early summer. (Photo: Winter Cutworm that appears to have been caught short by a sudden drop in temperature.)
One morning multiple 1”-2” white blotches appear on the screening of your porch or windows. They weren’t there the previous day, so they had to have been deposited during the night. What nocturnal creature is responsible and what exactly are they?
A close look reveals that each white patch consists of hundreds of minuscule white balls – eggs that an insect must have deposited. Their size, shape and coloring indicate that they were most likely produced by Owlet Moths or noctuids, members of the Noctuidae family. Owlet Moths make up over 25% of all butterflies and moths — there are 75,000 known species worldwide with thousands yet to be identified. Most adults are a fairly drab shade of brown and are well camouflaged with lines and spots that resemble tree bark or bird droppings. (Moth coloring often resembles the bark of the food plant its larvae prefer.) Owlet Moth larvae are relatively hairless and are referred to as cutworms or armyworms (they can occur in destructive swarms and cut the stems of plants). Several species are serious crop or garden pests.
A majority of the moths in this family are nocturnal and are attracted to light. After mating, female Owlet Moths produce between 300 and 1,500 eggs, depending on the species. Newly laid eggs are spherical and often cream color but may turn yellow, orange, pink, red or gray within a day. Those laid this fall will overwinter and larvae will hatch in the spring.
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