Andrena agilissima is an oligolectic species, feeding only on pollen of a few genera of Cruciferous vegetables (Brassicaceae species, as Brassica napus, Brassica rapa, Raphanus raphanistrum, Barbarea vulgaris and Sinapis species).
Andrena hattorfiana is an oligolectic species, feeding its young only on pollen of a few species of Dipsacaceae (Knautia arvensis, Scabiosa columbaria, Centaurea species).
Ancylandrena and Megandrena occur only in the desert regions of southwestern North America (Nevada, California, Arizona, Sonora, and Baja California), while Andrena is nearly worldwide.
Flowers are visited by many species of insects belonging to the order Hymenoptera, Diptera, Coleoptera, Lepidoptera and Heteroptera, outstanding species of Andrena (Andrenidae), Lasioglossum (Halictidae), Anthophora (Anthophoridae) and Bombylius (Bombyliidae).
He found a bee (Andrena) which had a sack-like parasite protruding from its abdomen which was identified by Dr. E. C. VanDyke as a female Stylops (order Strepsiptera).