Lactarius kauffmanii

Pileus
Cap 50-100 (125) mm broad, convex, nearly plane in age, sometimes with a depressed disc; margin incurved, becoming decurved to level, to slightly raised; surface viscid when moist, dingy brown, streaked with darker fibrils, margin lighter, the latter occasionally faintly zonate; context whitish, unchanging, soft at maturity, up to 15 mm thick near disc, gradually thinning towards margin; odor fungal to acrid; taste latently acrid.

Lamellae
Gills adnate, infrequently with a decurrent tooth, close, sometimes forked at the disc, cream colored, becoming buff-orange, up to 7 mm broad; latex white staining gills dull orange brown, drying olive grey; lamellulae in up to four tiers.

Stipe
Stipe 50-110 x 15-25 mm wide, more or less cylindrical, tapering below, sometimes with a pointed tip, hollow, brittle; surface glabrous, viscid when moist, uneven to scrobiculate, concolorous with the gills, i.e. buff-orange, bleeding a white latex darkening the stipe to dull orange brown where injured; partial veil absent.

Spores
Spores 7.5-9.5 x 6.5-8.0 µm, including ornamentation, subglobose to broadly ellipsoid, ornamentation a partial to nearly complete reticulum, amyloid; spores white to cream in deposit.