Bee of the Month


September 2020

Sunflower Chimney Bee

Diadasia enavata

 By Liam Cullinane, ISM Specialist

Photo Credit: bugguide

Sunflower chimney bee (Diadasia enavata) is a solitary ground nesting bee species that specializes on a subset of plants in the Asteraceae (Sunflower) family. Bees in the genus Diadasia are often called chimney bees because they create chimney-shaped structures on top of the entrance to their nest. 

Research suggests a few explanations for this behavior. The first is that these “chimneys” prevent debris or other insects coming into their nests. The other explanation is that they use the extra soil to plug their nest holes after they have laid their eggs. 

Bees in this species time their emergence from their nest when their host plants begin blooming (mid to late summer). They are very efficient at collecting pollen from these host plants (as seen in the picture) and provide invaluable pollination services in their ecosystems. 

They are one of the most common and widespread bee species in the Diadasia genus and can be seen across most of North America. Be on the lookout for these bees on sunflower blooms in late summer!

Squash bee

August 2020

Squash Bee

Peponapis pruinosa 

Squash bee is a solitary bee species that specializes on plants in the Cucurbita genus (squash and gourd plants). Because of this specialization, females only collect pollen from plant species in this genus (summer and winter squashes, pumpkins, gourds, etc.), hence why this bee’s common name is the squash bee. These bees are similar in size to honey bees (although they are a bit larger) and are sometimes misidentified as such, however, squash bee females nest in the ground in well-drained bare soil and males can often times be found resting in squash flowers. A defining characteristic of this bee species is their foraging behavior, collecting pollen around sunrise, when squash plants open their flowers. This bee species occurs throughout the United States and Mexico and is active in the mid-summer (June-August).