The cap of the porcini mushroom is 4-12 in diameter, at first hemispherical, then flat, the edge is sometimes slightly turned up. The surface is dry, from light brown to brown (dark brown, brownish, dark brown with a purple tint, reddish brown, beige, greenish, yellowish). In mature mushrooms, the top of the cap is darker than in young ones, the bottom is yellowish, yellowish-olive or yellowish-greenish, in young ones it is pure white. Stem of porcini fungus 5-15 cm long or more, 3-8 cm in diameter, thickened towards the base, often swollen, dense, light yellow, light or brown, with a mesh pattern, denser towards the top or in the middle. The pulp of the white fungus is dense, light, does not change color at the break. White fungus grows in dry, sparse birch groves, pine forests (porcini pine), oak and spruce forests (porcini spruce). In Russia, it grows mainly in the European part, the North-West zone (including the Leningrad region), in Western Siberia and the Caucasus. Collect until late autumn.