In Minnesota, there are eighty-seven described species within the genus Andrena and an additional four undescribed species. The majority of these species are active from spring to early summer (April to mid-June). Some Andrena species are among the earliest solitary bees to emerge in spring and can be observed visiting the first blooming plants such as Salix (willow). Andrena are one of the most common bee genera in woodlands in spring, visiting native flowering perennials followed by native shrubs such as Cornus (dogwood), Viburnum, and Sambucus (elderberry). Late summer and early autumn is another peak time for many Andrena species to be active. These end-of-season or autumnal species are pollen-collecting specialists (oligoleges) of plants in the family Asteraceae such as Helianthus (sunflower), Solidago and Euthamia (goldenrod), and Eurybia and Symphyotrichum (aster). These autumnal species often hold their wings out at a 45° angle while visiting flowers. 

All species in this genus nest in the ground and have solitary nests. Andrena nests are commonly found in yards and gardens. However, some species demonstrate strong preferences for nesting in specific types of soil. For example, Andrena asteris and Andrena barbilabris (photos below) are two species that prefer to nest in sand. Species that have a preference for a specific soil type often nest in aggregations (clusters of many solitary nests grouped together). Andrena are small-medium to medium-large and range in length from 5 to 18 mm (0.2 to 0.7 inches).