Brown birch bolete or Mottled bolete

Cap 5–15 cm across, at first spherical or hemispherical, later cushion-shaped. The surface is smooth or slightly wrinkled, dry or a little sticky in wet weather. Color ranges from grayish brown to dark brown, more rarely almost black.

Cap 5–10 cm, hemispherical in young mushrooms, then cushion-shaped. The surface is dry at first and slightly sticky in damp weather. The color is distinctive — a mouse-gray or dark brown background with scattered elongated light gray, yellowish or cream spots that resemble natural camouflage. The cap skin does not peel off.

The hymenophore is tubular. The tubes and pores are white, small in young mushrooms and wider in mature ones. When pressed, the pores turn slightly brownish, but there's never any bluing: unlike in the red-capped scaber stalks, the flesh doesn't blue even at the stem base.

The hymenophore is tubular, free, with a notch near the stem. White when young, then beige, light brown in mature mushrooms. The pores are small. They darken slightly when pressed.

Stem 8–18 cm tall, 1.5–3 cm thick, cylindrical, fairly long and slender compared with the cap. The surface is white or grayish, densely covered with dark, fibrous scales — the hallmark of the genus Leccinum. The stem is firm and fibrous.

Stem 12–18 cm tall, 2–2.5 cm thick, cylindrical or slightly tapering upward. White, with characteristic dark gray or brown fibrous scales — a typical feature of the genus Leccinum. In young mushrooms the scales are lighter, in old ones darker.

The flesh is firm and white; when cut it doesn't change colour or turns slightly pinkish, and after a few hours may become a little greyish or brownish. It darkens to grey-black only when cooked. The taste is mild and neutral. The cap skin doesn't peel.

The flesh is white, firm at first, soft and spongy with age. When cut: it turns pink in the cap, slightly blue in the tubes, and in the stem partly pink, partly green or bluish at the base. This multicolored reaction gave the species its name, “variicolor” (many-colored).

The smell is unobtrusive, pleasant and typically mushroomy. The aroma intensifies with cooking. When dried, the brown birch bolete takes on a rich scent that falls short of porcini but is noticeably better than most other pored mushrooms.

Smell faint, pleasantly mushroomy. Taste mild, not bitter.