There are many types of inchworms found in North America. These worms are not caterpillars and usually develop into moths. They’re of the Geometridae family and have a wide range of colors and patterns. Since they only have legs on the top and back of their bodies, they move by extending and retracting their bodies, causing them to loop in order to move. These creatures are also known as panworms, cankerworms, loopers, moth worms, and measuring worms. In this article, we listed some of the inchworms that you can find in North America. Keep reading to learn more about these tiny invertebrates.
12 Types of inchworms
1. Fall cankerworm
Scientific Name: Alsophila pometaria
The fall cankerworm is a type of inchworm found in North America, specifically in the eastern United States and Canada. They range in color from brownish-gray to green, with a dark stripe down the center of the back and white stripes on the sides. These creatures are usually about an inch long and, like all inchworms, have a gap between the legs on their head and back.
This species overwinters as eggs and emerges in the spring to feed until they become adults. Fall Cankerworms eat the leaves of a variety of plants, including apples, basswood, ash, maple, elm trees, oak trees, dogwood, and other hardwood trees.
2. Maple Spanworm
Scientific Name: Ennomos magnaria
The Maple Spanworm is a species of inchworm found in the northeastern United States and southern Canada. They’re about .7 inches long and have green bodies with cream and white stripes.
Maple Spanworms inhabit deciduous forests and swamps. Their larvae eat maple, birch, and willow leaves, as well as berries and plants like soybeans and sweet fern.
Adult moths are active during the fall months, breeding and laying eggs on their host plants. When spring arrives after winter, they emerge from their eggs, feed, and pupate. The larvae become adults in mid to late summer, when they mate and lay eggs to begin the cycle all over again.
3. Elm Spanworm
Scientific Name: Ennomos subsignaria
One of the inchworms you can find in North America is the Elm Spanworm. It’s a moth larva that can be found from Texas to Alberta.
As the name implies, these larvae feed on elm trees. They’re distinguished by their rusty head and dull black body, which can also be green or yellow, depending on the species.
These spanworms eat elm, apple, birch, maple, and oak trees. They can be seen feeding on the undersides of the leaves and pupating on the tips of branches or leaves. This species appears between the months of June and July.
4. Bruce Spanworm
Scientific Name: Operophtera bruceata
The Bruce Spanworm is a type of inchworm found in Canada and the northern United States, where it emerges as a larva from its eggs in May and June. Their color changes from pale yellow to dark green or brown with yellow stripes as they get older.
They eat a variety of trees, including willow, birch, oak, pine, maple, and poplar. After feeding until late June, these larvae will drop to the soil and pupate until the fall season, when they will emerge as adult moths.
5. Cabbage looper
Scientific Name: Trichoplusia ni
The cabbage looper is a type of moth larva named after its habit of eating cabbage family leaves. It’s an inchworm that takes the form of light brown moths with spots on their forewings.
The larva consumes a wide variety of cabbage family plants, including kale, radish, broccoli, mustard, rutabaga, and turnip, as well as celery, cucumber, tomato, squash, and lima beans. These species are found throughout the United States, where they’re considered pests due to the type of foliage on which they feed.
They’re also known as loopers because of the way they move. Since cabbage loopers only have front and back legs, crawling will require them to create a loop in order to move forward.
6. Hemlock looper
Scientific Name: Lambdina fiscellaria
The name “hemlock looper” comes from the fact that hemlocks are their preferred host plant, as well as their ability to loop around plants while feeding. The bodies of hemlock loopers are brownish or grayish, with gold or brownish stripes on their backs.
The larvae are voracious eaters, feasting on hemlock tree leaves as well as other plants like balsam fir and white spurge. They can grow up to 30 mm in length before pupating and emerging as adult moths.
7. Alfalfa looper
Scientific Name: Autographa californica
The alfalfa looper is a common North American moth with a distinct appearance. It’s an inchworm, which means it only has legs on the front and back of its body.
Its body is green with white stripes that can grow up to 1 inch long. This looper may resemble cabbage loopers, but their black-colored heads distinguish them from the other species.
Alfalfa loopers consume over 50 plant genera, but their primary food source is alfalfa. They lay their eggs on leaves or stems near where they will hatch; after about five days, the eggs hatch into larvae. The larvae then consume food until they’re ready to pupate into moths.
8. Linden looper
Scientific Name: Erannis tiliaria
Linden looper larva is an inchworm named after the linden tree, the insect’s most common host plant. The larvae have light brown or brownish-yellow bodies with yellow stripes down the sides and ten wavy black lines on the back.
This animal feeds primarily on apples, plum, birch, elm, oak, and other trees. You can find this species from Colorado to Canada, usually in habitats such as forest stands and woodlots where their host plants grow.
9. Omnivorous looper
Scientific Name: Sabulodes aegrotata
The omnivorous looper larva is a large species of inchworm that can reach a length of 2.5 inches. They’re usually yellow to light green in color, with a gold head. Dark lines can be seen all over its body.
Omnivorous loopers consume both the leaves and fruits of their hosts. They prefer to feed on trees like birch and willow, but they also eat shrubs like salmonberries and ironwood. These loopers usually pupate between the plant’s leaves for up to 4 weeks before becoming adults.
10. Blackberry looper
Scientific Name: Chlorochlamys chloroleucaria
The blackberry looper larva is another inchworm found in North America that moves in a looping motion. They’re common in Canada, Florida, the Rocky Mountains, and all the way to Mexico. These creatures are so named because they feed on the leaves of blackberry plants.
Blackberry loopers are green with a dark purple line down their backs. Their way of hiding from predators is by disguising themselves as newly sprouted twig by placing themselves on the branches. These loopers eat the leaves of blackberry plants as well as asters, sunflowers, and daisies.
11. Greater grapevine looper
Scientific Name: Eulithis gracilineata
The greater grapevine looper larva is a type of inchworm that you can find from Canada to Florida. It gets its name from the way it moves and its primary host plant. The larvae are greenish-brown in color, with small dots on each segment. This looper feeds on plants in the grape family, such as Virginia creeper and grapevines.
Greater grapevine looper larvae can mimic twigs and live in suburban, rural, and wooded areas. To avoid predators, they hang themselves from a branch while stiffening their bodies in an angled position, resembling a twig on a branch.
12. Pitch pine looper
Scientific Name: Lambdina pellucidaria
The Pitch pine looper larva derives its name from the fact that it’s most commonly found on pitch pines, which are evergreen trees native to North America. The larvae feed on the leaves of these trees and use them as host plants to lay their eggs on.
Pitch pine loopers have a large head and are brown and gray in color. They can grow up to 1 inch in length and can be seen from August to November. These inchworms pupate on the bases of the pine trees before emerging as moths.