This stately but nasty tasting bolete appears very early in the mushroom season under live oaks in California. Except for the telltale blue-brown staining of the pores, Boletus "Marshii" could easily be confused with some of the edible oak-loving boletes. Its flesh stains slighlty blue when cut, but it has a pale cap and cream colored pores (aging to olive) that resemble Boletus edulus, at least superficially. The specimens shown here are quite old, so their resemblance to the porcini has passed. This bitter bolete lacks the subtle perfume of its more delectible cousins. If you taste a bit of its flesh you will discover an acrid tannic aftertaste that would certainly destroy any dish you cooked with it. It probably isn't poisonous, but I can't imagine anyone wanting to eat enough to find out.