A large bolete with a pale greyish/brownish cap, often cracking with age.  Specimens are often misshapen.   Pores are yellow, staining blue when bruised, and the flesh stains blue when cut.  The stem is yellow with a reticulum near the top, and is slightly rooting.  It has a very bitter taste. 

Photograph a fresh specimen from top down and in side view, and underneath to show pores and full length of stipe.  Note habitat and substrate. Check for staining on cap and pores when bruised.  We also recommend cutting vertically through cap and stem to show flesh colour and any staining. 

Usually under oak or beech (possibly Rock-rose? - see Kibby, 2017)

Summer and autumn.

Status in Leicestershire and Rutland not known.