wild bees and native bees

Little metallic green bees: a stunning surprise in your garden

Agapostemon virescens, bicolored striped sweat bee in composite flower.

Have you ever seen a tiny bee with a metallic green body buzzing about your garden and moving at the speed of light? Here’s what that might be.

Inside: The metallic green bees in the genus Agapostemon are a vital part of many ecosystems, playing a critical role in pollination. In addition, they’re absolutely gorgeous, making any common flower sparkle in the sunlight.

Have you walked through your garden enjoying the flowers when you suddenly noticed a glint of light? Like an iridescent sequin or a thin strand of tinsel, it flashed green, then disappeared? If so, you may have seen a metallic green bee in the genus Agapostemon.

Nature’s gorgeous green gems

Actually, there are several groups of green bees in North America, many of which are found in the southern and eastern states. But the Agapostemon are uniquely spread across the entire continent, so no matter where you live, you have a good chance of spotting one. These bees are in the Halictidae family (sweat bees) and are native to North, Central, and South America.

Over 45 species of Agapostemon bees live in the Americas, all of which are important pollinators. They are some of the largest green bees in the US, measuring between 0.3 and 0.6 inches long. Both male and female Agapostemon have distinctive coloration, which can vary from bright green to blue-green or even blue-black. In addition, they often have green eyes.

They all look alike, more or less

Many of the metallic green bees are difficult to distinguish, but a few are easier. The bee in the top photo is a male Agapostemon virescens. These bees, spread over most of North America, are called bi-colored striped sweat bees because the male has a black-and-white striped abdomen, while the female abdomen is plain green.

Another unique species is the honey-tailed striped sweat bee, Agapostemon melliventris that lives in the southwestern US. The female has white and honey-colored stripes on her abdomen while the male has black and yellow stripes. Click here to see amazing photos of a mating lek, an aggregation of males waiting for females.

The life cycle of metallic green bees

Like all bees, metallic green bees undergo complete metamorphosis, meaning that they have four distinct life stages: egg, larva, pupa, and adult. Females lay their eggs in the ground, typically in a burrow or tunnel that they have created. The eggs hatch into larvae, which feed on a mixture of nectar and pollen that their mother has provided. Once the larvae have completed their development, they pupate and eventually emerge as adults.

The lifespan of an Agapostemon bee varies depending on the species and environmental conditions, but most adult bees live for several weeks to a few months. During this time, they will mate, lay eggs, and continue to pollinate plants in their habitat.

A metallic green bee, Agapostemon
A female metallic green bee. Note the green abdomen. Rusty Burlew

Habitat and homes of metallic green bees

Metallic green bees can be found in a variety of habitats, including meadows, prairies, forests, and gardens. They are solitary bees, meaning that they don’t live in colonies like honey bees or bumble bees. Instead, each female bee creates her own nest, which is typically located in the ground.

Although each female has her own nest, groups of female bees may share a “vestibule” similar to the lobby of an apartment building. The bees use the same front door, but each goes to her own digs once she’s inside.

They pollinate many kinds of plants

Metallic green bees are important pollinators, visiting a wide range of flowers in search of nectar and pollen. They are especially attracted to flowers in the mint family, such as thyme, oregano, and lavender. I also find them in composite flowers such as dandelions, burdock, and cosmos.

In addition to their role as pollinators, metallic green bees are also important indicators of the health of our environment. Because they are sensitive to changes in habitat and pesticide use, declines in their populations can serve as a warning sign of larger ecological problems.

Metallic green sweat bees enjoy flowers in the Asteraceae family, no matter where they are found.
A wide-legged green sweat bee (Agapostemon femoratus) enjoys flowers in the Asteraceae family, no matter where they are found. Notice the prominent green eyes. Rusty Burlew

The stamen-loving bees

The Latin name for the genus Agapostemon means “stamen loving.” Sure enough, these bees are often covered in pollen from head to tail, a sure sign they’ve been frolicking among the stamens.

Let us know when you see your first metallic green bee of the season. And don’t forget to send a picture!

Rusty
Honey Bee Suite

Bee with me . . .

Want to know more about male bees? Throughout the bee world, male bees have many similarities but many differences, too. See All buzz, no bite: the fascinating truth about male bees


About Me

My love of bee science is backed by a bachelor’s degree in Agronomic Crops and a master’s in Environmental Studies. I have written extensively about bees, including a current column in American Bee Journal and past columns in Two Million Blossoms and Bee Craft. In recent years, I’ve taken multiple courses in melittology and made extensive identifications of North American bees for iNaturalist. My master beekeeping certificate issued from U Montana. More here.

14 Comments

  • I saw my 1st green bee yesterday. Wow! It was trapped in my house until I wrangled her outside. Beautiful. Her colors appeared darker than the photos you show. I will bee watchful for them now. Sierra Nevada foothills nr Grass Valley, CA 1800′

    • Maddog,

      I’m so glad you saw one! To me, the green is quite dark unless they are in the sunlight. In some of my photos taken in shade, they look nearly black.

  • “they don’t live in hives like honey bees or bumble bees”

    colonies?

    [and feel free to remove after reading]

    • Sebastian,

      I don’t know where you live, but if you’re in North America, you could begin your bee education with “The Bees in Your Backyard.” That will introduce you to some of the 20,000 bee species that exist worldwide. If you’re on the east coast, you could try “Common Bees of Eastern North America (both by Wilson & Carril).” The second book has the exact green bee I’m writing about featured on the cover. Good luck. You’ve got a long row to hoe.

      • Christie,

        If you are agreeing with Sebastian, then I recommend the same books to you. All the hair and pollen on these insects immediately eliminate them as wasps, plus the structure of their wings and the proportions of their bodies. Seriously, take a look at some field guides to bees. There’s a whole other world out there and I don’t want you to miss it.

        • Is it possible Christie was agreeing with Rusty rather than Sebastian? I mean, I think we’ve all agreed that my taxonomic skills are lacking, but every single picture shows fuzzy beasties with pollen attached, and that’s pretty much THE one thing that makes a bee not a wasp.

          Also, maybe you should run a photo quiz—is it a bee?—is it a wasp? And throw in some hoverflies to be tricksy. Also, you can tell us down to species in the answer, but don’t make that part of the test, or I won’t get any right.

          • Roberta,

            Oh, dear. Yes, that’s possible, but it never occurred to me. I’ll tell her that.

            Thanks for the ideas. I’ve been thinking about doing another quiz, and that would be a good one. No species, just genera, or maybe not even that far.

  • Saw three beautiful little green sweat bees this afternoon here in Toronto, loving the allium. First time we’ve seen them in the 19 years of gardening.

    • Daniel,

      That is excellent. I wonder if they’re moving further north with the warm weather. And you’re right about allium; I’ve seen them there, too.

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