Here is an uncropped shot of the same fly. It and the larger of the leaves are all somewhere around an inch. It was certainly giant relative to the bee flies and leafcutters I'd been seeing that day.

This is either Pogonioefferia [Efferia] rapax or staminea. Both have this white hair conformation. P rapax is slightly larger which may give it the edge in a male. A 1 inch male in rapax is far more likely. Both are Colorado insects. I would have to be more familiar with your local Efferia to split the two from the photo.