When I first saw this I assumed B. nevadensis, but it just looks a little different from what I’m used to seeing in that species. The next closest I’m getting is B. morrisoni - out of documented range though in predicted climatic suitability (Williams et al. 2014).
Color is a richer yellow, top of head yellow, u-shaped yellow with black below on t3. Tried zooming in on face but can’t quite tell cheek length to width ratio or clypeus pitting to distinguish from nevadensis. Maybe a more discerning eye can.
Lens was foggy, sorry for poor photo quality
this species seldom seen in yard.
Crotchii? Feeding on branching phacelia
Bombus californicus
27 Mar 2021
CA, SBE Co., Morton Canyon
Visiting Calochortus plummerae on a south-facing slope in the southern San Bernardino Mountains