Lactarius kauffmanii var. kaufmanii
North American Species of Lactarius: 351. 1979.
Common Name: none
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.
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 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 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.
Scattered to gregarious in hardwood-conifer woods; fruiting from fall to mid winter along the coast; common.
This Lactarius is recognized by its medium size, a viscid dingy brown cap and contrasting buff orange gills and stipe; white latex that stains gill tissue dull orange brown and dries olive grey is also a helpful identifying character. Lactarius kauffmanii var. sitchensis known only from the type collection under Sitka spruce differs in possessing a yellowish spore print and a dark brown viscid cap with yellowish tones. Lactarius kauffmanii var. kauffmanii can be confused with another drab brown, viscid Lactarius, L. pseudomucidus. The latter, however, has gills that are whitish to cream yellow, not buff orange, and a brownish stipe. Another similar colored, sticky-capped Lactarius, L. argillaceafolius var. megacarpus, often found under oaks, is more robust in stature and differs in having a dry, non-scrobiculate stipe and pale yellowish latex.
Bessette, A.E., Harris, D.B. & Bessette, A.R. (2009). Milk Mushrooms of North America: A Field Guide to the Genus Lactarius. Syracuse University Press: Syracuse, NY. 298 p.
Hesler, L.R. & Smith, A.H. (1979). North American Species of Lactarius. University of Michigan Press: Ann Arbor, MI. 841 p. (Protologue)
Methven, A.S. (1997). The Agaricales (Gilled Fungi) of California. 10. Russulaceae II. Lactarius. Mad River Press: Eureka, CA. 79 p.
Methven, A.S. (1998). Lactarius in California and Beyond: Introduction to Subgenera and Species of Lactarius in California. Privately Published: Charleston, IL. 22 p.