The face and head are mostly black and there is usually a narrow, well-defined black interalar band across the thorax between the wings. The yellow hairs of the thorax and abdomen are lemony-yellow (vs. darker golden-tan in pensylvanicus). The abdomen (back body section) is mostly bright golden yellow (on T1-T4) with black tail tip (T5-). Wings are smoky. Males can be very similar to B. pensylvanicus but are smaller, with a longer malar space, consistent contrast between yellow T5 and black T6 (T6 color is variable in pensylvanicus), no black hairs on the rear of the thorax (scutellum), less black on the sides of the thorax posteriorly - behind the wing bases, and a better-defined narrow interalar band (vs. more diffuse and often broader band in pensylvanicus). Can be confused with borealis, but in that species the facial hairs are extensively yellow. Female fervidus in the Great Basin and elsewhere in the west often lack the black interalar band in which case the scutum is entirely yellow. Females of this color variety can be confused with B. morrisoni and even faced Pyrobombus specimens, but have entirely black facial hairs including the vertex (vs. yellow vertex in morrisoni and extensive yellow facial hairs in many Pyrombombus), a long malar space, and an entirely yellow T4 (this with black hairs in morrisoni). Faded ternarius with yellow replacing the usual red tergal hairs can be confusing, but in these the black hairs on the thoracic dorsum extend far posteriorly unlike fervidus.
U. of Michigan says "...found throughout the northern part of the United States down to the northern portions of Arkansas, Alabama, Georgia, and North Carolina. Populations are most concentrated in the North Eastern part of the United States."
discoverlife.org says "Quebec and New Brunswick to Georgia, west to the Pacific Coast" with the latter comment pertaining to californicus, often considered conspecific
Season
May to October
Food
Likes clover (Trifolium). The Hosts section of its Discover Life species page lists known floral associations based on specimen records and images.
Life Cycle
Emerges relatively late
Remarks
Has been considered to be declining but still often found, even in cities, as evidenced by the many Bugguide images. In the past very extensive collections of this species were made, likely from large clover fields, but in recent years it has usually been encountered in smaller numbers.
