Brown birch bolete or Slate 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.

The cap of the slate bolete reaches 5 to 15 centimeters across. When young it is hemispherical, becoming convex and cushion-shaped with age. The surface is smooth, dry or slightly slimy in rain, matte, often finely wrinkled in young mushrooms. The color is gray-brown, clay-brown or brownish-gray, sometimes with a faint violet tinge. The cap skin overhangs the margin slightly.

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. The tubes are long, with small round pores, dirty white or grayish in young mushrooms, turning gray-brown with age. When pressed, the pores may slowly darken. The hymenophore separates easily from the cap flesh, as is typical of boletes. The spore print is olive-brown.

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.

The stem is tall, dense and firm, 6 to 15 centimeters tall, whitish or grayish-white, covered along its whole length with characteristic dark — gray-brown to black — scales that form a granular, net-like pattern. At the base, the cut stem flesh often takes on a bluish-greenish tint. There is no volva and no ring. The firm, dense stem sets this species apart from the softer Leccinum species.

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, dense and firm, especially in young mushrooms, just as the name suggests. When cut it characteristically changes color: first turning pinkish or brownish, then gray and black; at the base of the stem it may turn green. The taste is mild and pleasant, with no bitterness. Thanks to its firm texture, the mushroom holds its shape well during cooking.

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.

The smell is faint, pleasant, typically mushroomy, with no sharp notes. The aroma is not a defining feature, so identification relies on the brown cap, the firm scaly stem, the color change of the cut flesh and the association with poplar or aspen.