Boletus appendiculatus Schaeff. ex Fr. syn. B. edulis f. appendiculatus Fr. Gelbfleischiger Steinpilz Bolet appendiculé Oak Bolete Cap 8–14cm, ochraceous with distinct bay to rusty flush particularly near the centre where irregular cracking may occur. Stem 110–125 x 34–37mm, lemon-yellow at apex darker below often with red patches, with a fine cream to pale lemon-yellow net. Flesh white to pale yellow, turning blue on cutting at apex of stem and often ochraceous rust at base. Taste pleasant, smell like puffballs. Tubes lemon-yellow bruising faintly greenish blue. Pores initially lemon-yellow becoming slightly rusty and expanding with age. Spore print olivaceous snuff-brown. Spores subfusiform, 12–15 x 3.5–4.5µ. Habitat with broad-leaved trees, associated with oak in the South of England. Season late summer to early autumn. Rare, more frequent in the South of England. Edible – excellent. Distribution, America and Europe.