Bombus ternarius, commonly known as the orange-belted bumblebee or tricolored bumblebee, is a yellow, orange and black bumblebee. It is a ground-nesting social insect whose colony cycle lasts only one season, common throughout the northeastern United States and much of Canada. The orange-belted bumblebee forages on Rubus, goldenrods, Vaccinium, and milkweeds found throughout the colony's range. Like many other members of the genus, Bombus ternarius exhibits complex social structure with a reproductive queen caste and a multitude of sister workers with labor such as foraging, nursing, and nest maintenance divided among the subordinates.