Barbarea vulgaris (Yellow Rocket) introduced
(information is limited primarily to Andrenid bees; some observations are from Hilty and Lewis as indicated below, otherwise observations are from Krombein et al.; bees suck nectar or collect pollen, while the butterfly sucks nectar)

Bees (short-tongued)
Andrenidae (Andreninae): Andrena arabis (Kr), Andrena ceanothi (Kr), Andrena erigeniae sn (Kr), Andrena forbesii (Kr), Andrena hippotes (Kr), Andrena imitatrix imitatrix (Kr), Andrena integra (Kr), Andrena miranda (Kr), Andrena nigrifrons (Kr), Andrena rugosa (Kr), Andrena sigmundi (Kr), Andrena spiraeana (Kr), Andrena ziziae (Kr)

Butterflies
Pieridae: Pieris rapae sn (H, Lw)