This summer, Bill and I have been inundated with little fast moving, yellow-tinged flies that people have for years called “sweat bees.”

Well, this article sets the record straight.

Hover flies (Episyrphus balteatus), also known as flower flies, sweat bees or flies, are members of the Syriphidae (syrphids) classification of flies belonging to Diptera family, meaning they have two wings as all flies do.

Adults feed on pollen and nectar from all kinds of flowers, but the larvae, called maggots, are voracious predators of aphids, caterpillars, leafhoppers, plant hoppers, mealy bugs and thrips, to mention only a few. They are so efficient at eating, they can be purchased commercially. Each larva can consume up to 400 aphids during development, “when syrphid larvae are abundant, they may reduce aphid populations by 70-90%,” according to the Cornell Hover Fly Bio Control Fact Sheet.

Hover flies dart in and out of flowers, as well they zip around people, licking sweat salts that they need. They are from ¼- to ¾-inch long, yellow and black stripes, hairy with long, thin abdomen, short stubby antennae and behind the wings are short stubby “halters” that look like a club, used for balance when flying. They mimic bees and wasps for protection, but they do not sting or bite.

The adults lay tiny single white eggs on leaves near aphid colonies. These hatch in 2 to 3 days. Maggots hatch out white, cream or brown and with their hooklike mouths begin to eat. Some pupate on leaves, while others pupate in the ground.

They overwinter as larvae or pupae. The lifecycle is completed in 2 to 4 weeks. Generation times depend on weather temperatures, food sources and species and may complete as many as 5 to 7 generations each year.

Some species of syrphid flies are not only predators but are parasitoids, laying eggs inside a host that eats the host for food. No matter the kind these insects are invaluable for insect control. They are highly susceptible to insecticides and pesticides, so great care and caution must be used when applying.

Syrphids can be attracted to your home by planting many constantly flowering plants for summerlong food sources for adults. They love white compound flowers, alyssum is the favorite.

Queen Anne’s lace, wild mustard, coriander, dill and other small-flowered herbs are important to them. Also, to attract syrphid flies supply windbreaks as protection, plant blooming cover crops and the flies will come.

As I read the sources for this article, I now understand that these flies are an important part of my garden, and we are stewards of a more in-depth view of gardening than I had ever known.

For photos and more, go to https://go.osu.edu/hoverorsweat.

Hughes is an Ohio State University Extension Master Gardener Volunteer in Mahoning County.