Bitter Beech Bolete Boletus calopus Pers. (illustrated 45% life size) Cap 5–14cm across; smoke-grey or flushed olivaceous; slightly downy then smooth, sometimes slightly cracked or scaly at centre with age. Stem 70–90×35–45mm; lemon-yellow at apex, elsewhere red, although frequently brown at base, covered with white or straw-coloured network; robust. Flesh pale straw-coloured to pale lemon-yellow, becoming whitish immediately on cutting then flushed blue, especially in the stem apex and over the tubes, sometimes patchily red at the base of the stem; taste bitter, smell strong. Tubes dirty sulphur-yellow, bruising bluish-green. Pores colouring similar to tubes, also bruising bluish-green. Spores 12–16×4.5–5.5¼, subfusiform. Spore print olivaceous walnut-brown. Habitat in mixed woodland, particularly with beech or oak; late summer to autumn. Occasional. Not edible very bitter.
