Thursday, December 13, 2012

Native Bee Spotlight: Green Sweat Bees ~ Agapostemon spp.

Green Sweat Bees (Metallic Green Bees) ~ Agapostemon spp.

Green Sweat Bees are one of the most brightly colored native bees in our area. A bright emerald green head and thorax, with a striped abdomen of pale to bright yellow. Some females in this genus are entirely green, and often difficult to distinguish from bees in the Augochlora genus.

We see Green Sweat Bees in late May, some of the first females visit Ohio Spiderwort (Tradescantia ohiensis) to collect and feed on pollen. No nectar is offered by this native. Read about other visitors to Spiderwort here.

Green Sweat Bees nest in the ground, building long vertical nest cavities. Most are solitary nesting like the majority of native bees, but some species share the same nest entrance but build their own cavities.

Another good source of pollen for Green Sweat Bee females in early spring is Great St. John's Wort (Hypericum pyramidatum).

Green Sweat Bees are short tongued, so they visit shallow or easily accessible flowers for nectar. They like to visit both the prairie native Hoary Vervain (Verbena stricta), found in dry, sunny locales as well as the wetland native Blue Vervain, Verbena hastata for nectar.
Visiting Blue Vervain for nectar.

Look for Green Sweat Bees on Coneflower (Echinacea) species. Females collected pollen and feed on nectar on our Pale Purple Coneflower.

They will investigate the flowers of Wild Bergamot, possibly feeding on pollen but cannot reach the nectar in the long flower tubes.
Culver's Root (Veronicastrum virginicum) is a late summer favorite of Green Sweat Bees. The numerous shallow white tubular flowers provide an abundance of nectar.

Look for Green Sweat Bees in late summer on Cup Plant (Silphium perfoliatum) as well as many of the fall flowering Asters.

These native bees are fast moving and camera shy. It's often difficult to capture them because their flower visits are very short, so have your camera ready if you spot one.






References:
Attracting Native Pollinators: The Xerces Society Guide, Protecting North America's Bees and Butterflies