Look for aster mining bee (Andrena asteris) in fall when the temperatures begin to drop and roadsides become ablaze with goldenrods and asters. The species is common throughout New England and can be found in a wide range of habitats from gardens to meadows to old fields to coastal dunes. This is a bee that we can expect to see pretty much anywhere if we watch fall goldenrods and asters for long enough.
One generation per year, active from late-August through October.
Widespread across northeast, with core range in more northern latitudes.
Size ≈ honey bee
Females: Medium-sized, robust Andrena. Face with pale hairs, thorax ranges from sand to ochre-colored with strongly banded abdomen on all segments. Scopae on hind leg “armpits” often busting with yellow aster pollen.
Males: much like female, but smaller and hairier (often less sandy orange hairs than female). Face with a yellow clypeus and yellow parocular area. Often readily observed mating with females on flowers.
- A. braccata has no hair band on T1, and broken band on T2, and holds its wings out compulsively when foraging.
- A. simplex/placata have relatively gray color (vs. yellowish coloration of A. asteris), and daintier build (A. asteris is stocky)
A. asteris apparently nests in a wide range of soils, though its nests have never been formally described. A. asteris is known to aggregate where conditions are suitable, often in compacted soils like boat ramps or earthen parking lots. Females plug nests upon departure and “sonicate” back into the soil upon return.
Fall-blooming Asteraceae, especially goldenrods (Solidago spp., Oligoneuron rigida, and Euthamia spp.), fleabanes (Pluchea purpurascens), and wood asters (Symphyotrichum spp. and Eurybia spp.).
Nomada banski and Sphecodes johnsonii are suspected brood parasites often observed at active aggregations.
Text last updated:
February 22, 2023