Dentinum umbilicatum (Peck) Pouz.
Cap (Pileus): 2.5 – 7.0 cm broad, convex at first, then planar with an abrupt deep navel and finally funnel shaped; margins decurved at first, then wavy and flaring, undulating and convoluted; surface dry, unpolished, velvety, wrinkled, occasionally with pimples; colour pale pink becoming paler towards the margins; context 1 cm at the junction of the stipe, solid, firm, white, not changing when bruised; taste mild; odour indistinct.
Spines or Teeth (Hymenium): horizontal; spaced close to crowded; 0.5 – 1.0 cm long, becoming shorter towards the margins; colour white at first then with a pinkish hue and finally yellowish orange when mature.
Stalk (Stipe): 2 – 5 cm long X 1.5 – 1.5 cm wide, equal, flexuous, central; surface dry, unpolished, with minute pimples especially towards the apex; colour white with a light yellow hue, bruising orange; context firm, solid, dry, white with some orange bruising when cut.
Spore print white; spores 8 – 10 X 9 µm, subglobose, smooth, inamyloid; no apparent hymenial cystidia; hyphae with clamp connections.
Comments: Hydnum umbilicatum is easily confused with Hydnum repandum though H. repandum has a larger, darker cap, a relatively shorter stipe, bruises deep orange and lacks an abrupt deep navel on the cap. The two mushrooms can be differentiated by the spore size though there is much overlap. Hydnum umbilicatum generally has somewhat larger spores than H. repandum var. repandum. To confuse things further, H. repandum var. macrosporum and H. washingtonianum have spores that are similar in size and shape to those of H. umbilicatum. Hydnum washingtonianum has not yet been reported from B.C. but has been reported from the Pacific Northwest of the United States.
Habit, Ecology, Habitat and Range
Hydnum umbilicatum fruits in troops on the ground and is associated with Douglas-fir (Pseudotsuga menziesii), Pacific silver fir (Abies amabalis), sitka spruce (Picea sitchensis) and western hemlock (Tsuga heterophylla) forests throughout the province. It is usually found in areas where soil moisture accumulates and fruits in troops from mid August to late November and is often found among sphagnum and other mosses in conifer forests. This mushroom has been collected in the southern coast, Vancouver Island, the south and central interior.
Hydnum umbilicatum is edible and choice, but because of its small size is rarely harvested commercially. However, if cooked in iron, it can be bitter. It is, for the most part, regarded simply as a smaller version of Hydnum repandum. There are few records of this species outside the northwestern North America, suggesting that it is an endemic species. Further biogeographic studies are needed to determine if this observation is true.
Arora, D. 1986. Mushrooms demystified. Ten Speed Press. Berkeley, Ca. 959 pp.
Castellano, M.A., E. Cázares, B. Fondrick, and T. Dreisbach. 2003. Handbook to Additional Fungal Species of Special Concern in the Northwest Forest Plan. Gen. Tech. Rep. PNW-GTR-572. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 144 pp.
Hall, D., and D.E. Stuntz. 1971. Pileate Hydnaceae of the Puget Sound area. I. White-spored genera: Auriscalpium, Hericium, Dentinum and Phellodon. Mycologia 63: 1099-1128.
Tylutki, E.E. 1987. Mushrooms of Idaho and the Pacific Northwest. Vol 2. Non-gilled Hymenomycetes. Univ. Idaho Press. Moscow, Idaho. 232 pp.
