Leccinum scabrum (Fries) S. F. Gray Birch rough stalks or Brown birch-bolete.
Cap: width 45-150 mm. Stem: length 70-200 mm; width 20-30 mm.
Description: [Plate 1].
Cap: convex and becoming only slightly expanded at maturity, pale brown, tan or buff, soft, surface dry, but in wet weather becoming quite tacky, smooth or streaky-wrinkled and cap-margin not overhanging the tubes.
Stem: white, buff or greyish, roughened by scurfy scales which are minute, pale and arranged in irregular lines at the stem-apex, and enlarged and dark brown to blackish towards the base.
Tubes: depressed about the stem, white becoming yellowish brown at maturity, with small, white pores which become buff at maturity and bruise distinctly yellow-brown or pale pinkish brown when touched.
Flesh: watery, very soft in the cap lacking distinctive smell and either not changing on exposure to the air or only faintly becoming pinkish or pale peach-colour.
Spore-print: brown with flush of pinkish brown when freshly prepared.
Spores: very long, spindle-shaped, smooth, pale honey-coloured under the microscope and more than 14 µm in length (14-20 µm long × 5-6 µm broad).
Marginal cystidia: numerous and flask-shaped. Facial cystidia: sparse, similar to marginal cystidia.