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It’s a bird…it’s a plane…no, it’s a moth!

By Jane Bielecki, Master Gardener

What are hummingbird moths and where do they come from? To keep this article short and appropriate for newspapers, the easiest answer is, hornworms.

Hornworms are some of the largest caterpillars in North America. All hornworms have the defining characteristic of a notable horn on their hind end, at least during the first stages of development. These horns are flexible, but do look formidable.

Of the 120 species on the continent, only a few may become problematic and cause damage to plants. Some examples include the tobacco hornworm, the tomato hornworm and the catalpa sphinx.

The adult version of the hornworm caterpillar is a moth. They are know as sphinx moths or hawk moths. These moths are strong fliers, with heavy bodies. They feed on nectar from deep-lobed flowers like phlox. When active during the day, these moths are sometimes called hummingbird moths.

Given the size, shape, flight style and patterns of hummingbird moths, they can easily be mistaken as hummingbirds. Their wings beat too quickly to be seen, as they rapidly fly from flower to flower. They maneuver through the air, much like a hummingbird, as they feed on nectar.

One of the most widely distributed sphinx moths in North America, is the white-lined sphinx moth. It is found in this area, but is more common in the west.

The white lined sphinx moth can have a wingspan of almost four inches. It is mostly gray in color, with a defining large, white stripe on the forewing. It will have thinner white lines on the wings and body, and light pink markings, as well.

The larvae of the moth can vary in color, from bright green to black. They can grow to be almost three inches long, and feed and grow on a wide variety of plants. Some of the more common plants enjoyed by this hornworm, include portulaca, evening primrose and grape. Each year, two generations are produced, with the pupa overwintering in the soil.

Another common species of sphinx moth in this area, is the snowberry clearwing moth. It is found mostly in eastern North America. This moth is smaller than the white-lined sphinx moth and its wingspan is about two inches.

The body is mostly covered in yellow hair, with a thick black band approximately 3/4 through. The wings are lined with a rusty-maroon color and clear in the center.

This moth darts quickly between flowers while feeding during the day. Although they will drink nectar at many different flowers, they enjoy petunias. They are also commonly seen feeding on butterfly bush, butterfly weed, purple conefl ower, bee balm and Joe-pye weed, acting as pollinators of many plants.

The hornworm caterpillars and the adult hummingbird moths they turn into, are strange, fascinating and lovely. Planting flowers they favor, is an excellent way to attract these insects for pollination and garden entertainment.

Happy Gardening!