WHITE RIVER JUNCTION – Willows (genus Salix) are pollen powerhouses in April. From river banks to roadside ditches, these fast-growing shrubs provide abundant food for early spring pollinators. Their inconspicuous, greenish flowers are visited by a variety of different bees and other insects and are likely the primary pollen source for several specialist bees.
These specialist bees are only active for a few weeks in the spring when willows are blooming, from which they frantically gather pollen to provision the next generation that develops over the summer in an underground tunnel.
In Vermont, at least eight different species of mining bees (genus Andrena) are considered willow specialists, each with slightly different preferences in nesting substrate, climate, and/or willow species. Like most mining bees, they can be tricky to identify from photographs, though several species in this group are quite distinctive. Learn about each species at val.vtecostudies.org/projects/vtbees/andrena-willows/ then go out to find any in the neighborhood and add to the Vermont Wild Bee Survey, inaturalist.org/projects/vermont-wild-bee-survey
Spencer Hardy works at the Vermont Center for Ecostudies