|Major Groups > Boletes > Suillus > Suillus cavipes|
by Michael Kuo
This is a fascinating and gorgeous Suillus species, found under tamarack (Larix laricina) throughout the range of the host tree. It is fairly unmistakable, featuring a dry, densely hairy brown cap, a beautifully yellow or greenish yellow pore surface, and a stem that is almost always hollow in the base when mature.
Ecology: Mycorrhizal with tamarack (Larix laricina); growing alone or gregariously; fall; northeastern and northern North America. Arora (1986) documents Suillus cavipes under "larch" (probably Larix occidentalis) in Oregon and Washington.
Cap: 3-10 cm; convex becoming broadly convex or flat, sometimes with a broad central bump; fairly dry; densely hairy with whitish to brownish hairs and fibers; yellowish brown, reddish brown, or brown; usually with white partial veil remnants on the margin.
Pore Surface: Yellow or greenish yellow; not bruising; pores angular and radially arranged (but not boletinoid), about 1 mm across; tubes to 5 mm deep.
Stem: 4-9 cm long; .5-1.5 cm thick; sometimes somewhat bulbous; yellow and smooth toward the apex, brownish and hairy below; sometimes with a fragile ring; hollow in the base.
Flesh: White to yellowish; not staining on exposure.
Odor and Taste: Not distinctive.
Chemical Reactions: Cap surface red with ammonia; black with KOH; negative with iron salts. Flesh sea green with ammonia; negative or yellowish with KOH; negative with iron salts.
Spore Print: Olive brown to brown.
Microscopic Features: Spores 7-10 x 3.5-4 µ; smooth; subfusoid. Clamp connections present.
REFERENCES: (Opatowski, 1836) Smith & Thiers, 1964. (Smith & Thiers, 1964; Snell & Dick, 1970; Smith & Thiers, 1971; Grund & Harrison, 1976; Smith, Smith & Weber, 1981; Arora, 1986; Phillips, 1991/2005; Lincoff, 1992; Both, 1993; Barron, 1999; Bessette, Roody & Bessette, 2000; McNeil, 2006; Miller & Miller, 2006; Kuo, 2007.) Herb. Kuo 09120401.
Boletinus cavipes is a synonym.
Further Online Information:
Cite this page as:
Kuo, M. (2004, November). Suillus cavipes. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/suillus_cavipes.html