Agapostemon / Green Sweat Bee
Female Agapostemon texanus visiting a Sphaeralcea (desert mallow) flower. © Rollin Coville
Female Agapostemon on Mexican hat (Ratibida columnifera) in Northern Arizona. © Elizabeth Buckalew
Agapostemon virescens on Persicaria longiseta in Temple Hills, Maryland. © Barbara Thurlow
Common Name: Green Sweat Bee
Females of some species are entirely bright green, whereas others have a bright green head and thorax and contrasting black and white striped abdomen. Agapostemon males typically have a bright green head and thorax in combination with a striking black and yellow striped abdomen.
The female carries pollen in brushes of specialized hairs, called a scopa, on her hind legs.
Females mate in late summer/early fall and hibernate, usually in their old nests, over winter. They emerge in spring ready to found new nests of offspring.
Agapostemon are generalists, visiting many plant species to obtain pollen and nectar. As true generalists, Agapostemon can be excellent crop pollinators, provided that supplemental forage and nest sites are available. They are known to be effective pollinators of strawberry, watermelon, and even squash plants.
While, like other members of the subfamily, Halictinae, they are commonly referred to as “sweat bees,” Agapostemon species are not actually attracted to human perspiration. Two other main bee genera in the subfamily Halictinae (sometimes collectively referred to as “halictids”), Halictus and Lasioglossum, are known to be attracted to human perspiration, which they drink for the salt content. Due to their close familial relationship, however, the common term “sweat bee” has come to describe all the genera in this subfamily.
These striking, colorful bees are frequent visitors in spring and summer to gardens across most of the U.S., especially when attracted by an abundance of floral resources and sufficient ground nesting areas.
Size: Small to medium sized slender bee, approximately 1/3 inch in length.
Found primarily in the Americas, with the greatest abundance of species occurring in North America. The genus is widespread across North America, being most diverse and abundant in temperate regions and in deserts of the southwest United States.
Mated females from the previous fall emerge in spring to found their nests; new female and male offspring appear from early through late summer.
Pollinated Garden Crops Include
Additional Flowers Visited in Natural Areas
Psorothamnus (dalea, smoketree)