N. Amer. Sp. of Lactarius, p. 76. 1979.
Common Name: none
Misapplied name: Lactarius sanguifluus
Cap 5.0-12 cm broad, convex, margin inrolled when young, becoming plano-convex to shallowly infundibuliform in age; surface viscid when moist, banded concentrically with shades of orange; often developing green discolorations in age; flesh thick, brittle, bleeding a sparse, dark red latex when cut; taste and odor mild.
Gills decurrent, narrow, close to crowded, dull orange, bleeding a dark red latex.
Stipe 2-5 cm tall, 1.0-2.5 cm thick, solid and brittle when young, hollow in age, equal to tapered at the base; surface smooth, unpolished, dull orange-buff, bruising green where handled.
Spores 7-9 x 6-7.5 µm, ovoid with amyloid reticulations; spore print pale yellow.
Scattered to gregarious under Douglas fir; fruiting from late fall to mid-winter.
Lactarius rubrilacteus closely resembles L. deliciosus. Both species have orange to orange-red zoned, shallowly, infundibulate caps and tend to develop green discolorations in age, but Lactarius rubrilacteus has a dark reddish rather than carrot-orange latex. In addition, Lactarius rubrilacteus is associated with Douglas fir (Pseudotsuga menziesii) while L. deliciosus is found with pines (Pinus).
Methven, A.S. (1997). The Agaricales (Gilled Fungi) of California. 10. Russulaceae II. Lactarius. Mad River Press: Eureka, CA. 79 p.
Hesler, L.R. & Smith, A.H. (1979). North American Species of Lactarius. University of Michigan Press: Ann Arbor, MI. 841 p.
Nuytinck, J., Miller, S.L. & Verbeken, A. (2006). A taxonomical treatment of the North and Central American species in Lactarius sect. Deliciosi. Mycotaxon 96: 261-307.
Nuytinck, J., Verbeken, A. & Miller, S.L. (2007). Worldwide phylogeny of Lactarius section Deliciosi inferred from ITS and glyceraldehyde-3-phosphate dehydrogenase gene sequences. Mycologia 99(6): 820-832.