By Anita Collins, Ph.D. USDA, ARS retired
Pennsylvania has about 400 species of native bees. Bumble bees, sweat bees, carpenter bees, squash bees and many more, some with no common name. Honey bees are an invasive species, introduced to the Americas by the colonists.
Most native bees are solitary, one mated female makes a nest, collects pollen and nectar, and lays an egg on these provisions. She only lives about six weeks. The young bees develop on their own and emerge the following summer. Bumble bees are social: a mated queen starts a nest and raises a few daughters who help rear more sisters. The family grows in number over the summer, raises new queens who mate in fall, then the nests die off.
The mated queens find a safe place for the winter and starts again. Each type of bee has a typical nest either in the ground, in stems, or in holes in wood. Bees are hairy to collect pollen and have long tongues to suck nectar. Most of them specialize on one type of native plant, sometimes only one species, and are active when their plants are in bloom.
Native bees and native plants need each other!
Top: Sweat Bee
Bottom Left: Bumble Bee. Bottom Right: Leafcutter Bee
Photos courtesy of Bonnie Pancoast