Boletus calopus var. frustosus Snell & Dick

This massive, bluing Bolete fruits in the higher elevations of Sierra Nevada, early in the season --  Aug/Oct. In the typically dry Sierra weather, the pileus tends to become exceedingly aerolate and hard, bearing superficial resemblance to Neolentinus ponderosus. It's bitter taste is unmistakable. It seems quite close to Boletus coniferarum, and is probably only a distant relative of the European B. calopus var. calopus.