Hydnum umbilicatum Rep. N.Y. St. Mus. 54: 171. 1901.
Common Name: Hedgehog
Synonym: Dentinum umbilicatum (Peck) Pouz.
Cap 2.5-5 cm broad, convex, becoming, broadly convex, the disc noticeably indented or umbilicate; margin at first incurved, then decurved, sometimes wavy; surface dry, smooth, occasionally roughened or with appressed squamules, cream-buff to tawny, darker in age; flesh cream-buff, moderately thick, bruising slowly dull-orange; odor and taste mild.
Teeth 5-7 mm long, cream-buff, slowly darkening to dull-orange, adnate or narrowly depressed at stipe.
Stipe 2.5-6 cm tall, 0.5-1.0 cm thick, equal to narrowed at the base, attachment usually central; surface dry, cream-buff (lighter than the pileus), bruising dull- orange; veil absent.
Spores 8-10 x 7.5-8.5 µm, subglobose, smooth; spore print white.
Scattered to gregarious in hardwood/conifer woods; often common under tanbark oak (Lithocarpus densiflorus) and madrone (Arbutus menziesii), sometimes with Douglas fir (Pseudotsuga menziesii); fruiting from mid-winter to early spring.
Edible and good.
Like its larger cousin Hydnum repandum, H. umbilicatum fruits late in the mushroom season, but while H. repandum typically is assoicated with pines, e.g. Pinus muricata (Bishop pine), in our area, H. umbilicatum tends to be found with a mix of hardwoods (see Habitat) often at the same time as Cantharellus tubaeformis (yellow-foot/winter chanterelle) and Craterellus cornucopioides (black chanterelle). Hydnum umbilicatum and H. repandum are similarly colored, but can be told apart through a combination of macroscopic and microscopic characters: Hydnum umbilicatum is smaller, more slender, has an indented or umbilicate cap, and the hymenium is not subdecurrent as is sometimes the case in H. repandum. Finally, the spores of Hydnum umbilicatum are significantly larger than those of H. repandum.
Coker, W.C. & Beers, A.H. (1951). The Stipitate Hydnums of the Eastern United States. The University of North Carolina Press: Chapel Hill, NC. 211 p.
Desjardin, D.E., Wood, M.G. & Stevens, F.A. (2015). California Mushrooms: The Comprehensive Identification Guide. Timber Press: Portland, OR. 560 p.
Hall, D. & Stuntz, D.E. (1971). Pileate Hydnaceae of the Puget Sound Area. I. White-Spored Genera: Auriscalpium, Hericium, Dentinum and Phellodon. Mycologia 63(6): 1099-1128.
Peck, C.H. (1902). Report of the State Botanist 1901. N. Y. State Mus. Bull. 54: 931-991. (Protologue)
Smith, A.H. (1949). Mushrooms in their Natural Habitats. Sawyer's Inc: Portland, OR. 626 p.