Hickory Tussock Moth
Most tussock moths, such as this Hickory Tussock Moth (Lophocampa caryae), are densely covered with hair-like structures called setae that bear microscopic barbs. Many people are sensitive to these setae and get an itchy rash if they handle a Hickory Tussock Moth. Even touching the cocoon of a tussock moth can cause irritation, as the setae are woven into it. Many tussock moths display warning coloration with their black, white, red, orange or yellow setae. What looks like two Hickory Tussock Moth larvae in the photograph is actually one adult caterpillar (left) and its shed skin (right). You can find these larvae feeding on hickory, walnut, ash, oak and many other trees in the woods right now. After spending the winter pupating in a cocoon in the leaf litter, a small spotted, tan moth emerges.
Noctuid Moth Larva
The striped caterpillar that is crawling along the surface of fresh snow is the larval stage of a noctuid or owlet moth (species unknown). Noctuids are dull-colored, medium-sized, nocturnal moths that are attracted to lights in the summer. They usually possess a well-developed proboscis (mouthpart) for sucking nectar. You may be familiar with the common garden pests, cutworms, which are also noctuid larvae. How this larva survives freezing temperatures I do not know, but I have seen several dozen at a time crawling around on top of the snow. Note: Jean Harrison, a fellow nature lover, just identified this larva as Noctua pronuba, a winter cutworm also known as the greater yellow underwing (moth), a recent immigrant from Europe.
Woolly Bears
Legend has it that the more black at either end of a woolly bear, the harder the winter that lies ahead. Truth be known, the woolly bear caterpillar (larval stage of the Isabella Tiger Moth) molts its skin up to six times, and each time a brown section is added; thus, the longer the summer, the greater the ratio of brown to black on a woolly bear. A mostly-brown caterpillar is more an indication of an early spring or late fall, rather than a forecast of the coming winter’s severity!
Cecropia Moth Caterpillar Molting
The caterpillar, or larval, stage of a butterfly or moth is the only stage in which the insect has chewing mouth parts. Hence, it is the stage during which a great deal of eating takes place. As the caterpillar eats, it grows larger, and eventually molts its skin, revealing a new, larger skin underneath the old. A cecropia caterpillar molts four times before spinning its cocoon and pupating. The cecropia caterpillar in this photograph has just molted its skin, which is attached to the plant just above the caterpillar’s head. If you look closely, you can see where the colored tubercles were. Within an hour of when this photograph was taken, the caterpillar had eaten its skin.
Monarch Butterflies
The third and fourth generations of the monarchs that migrated from New England to central Mexico last fall are arriving in New England, mating and laying eggs. The eggs are hatching, and some of the larvae, or caterpillars, are well on their way to adulthood. This larval stage of their metamorphosis lasts about two weeks, and is the only stage during which monarchs have chewing mouth parts. The caterpillars take advantage of this by consuming both the leaves and flower buds (see photograph) of common milkweed practically non-stop, increasing their body mass up to 2,000 times.
Naturally Curious with Mary Holland 
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