SUILLUS GRANULATUS (Fries) Kuntze, Rev. Gen. Pl. 32:535. 1898
Boletus granulatus Fries, Syst. Mycol. 1:385. 1821.
Rostkovites granulatus (Fries) Karsten, Rev. Mycol. 3:16. 1881.
Illustrations
Kawamura, S., Icones of Japanese Fungi, pl. 232.
Lange, J. E., and M. Lange, 600 Pilze in Farben, p. 189.
Leclair, A., and H. Essette, Les Bolets, pl. 9.
Romagnesi, H., Nouvel Atlas des Champignons, pl. 120A.
Singer, R., Die Rohrlinge, Teil 1, pl. VII, figs. 9-13, pl. VIII, figs. 1-10.
Smith, A. H., The Mushroom Hunter's Field Guide, p. 90, pl. 56.
Smith, A. H., and H. D. Thiers, A Contribution Toward a Monograph of North American Species of Suillus, pls. 43, 44.
Smith, A. H., and H. D. Thiers, The Boletes of Michigan, pl. 32.
Snell, W. H., and E. A. Dick, The Boleti of Northeastern North America, pl. 20.

Pileus 5-12 cm broad when mature, convex, becoming broadly convex to plano-convex to plane; surface viscid to glutinous, glabrous or streaked or spotted with brown ("cinnamon") on a pale buff ("pinkish buff" to "cinnamon-buff") ground color, in age more or less cinnamon ("orange-cinnamon") overall, immature specimens often pallid for a long time; margin naked to minutely tomentose, in age often areolate, incurved, becoming decurved, no conspicuous cottony roll of veil tissue. Context 1-2 cm thick, whitish when young, unchanging or becoming pale yellow, with a watery green line above the tubes. Taste mild to acid; odor mild to slightly fragrant.

Tubes up to 1 cm long, adnate to subdecurrent, pallid at first, but soon pale yellow, becoming dingy yellow, not staining when bruised; pores small, about two per millimeter, or in old basidiocarps one per millimeter and somewhat boletinoid to merely elongated, pale honey yellowish, in age brownish spotted, staining dingy cinnamon when bruised, in very young stages beaded with droplets of a cloudy liquid.

Stipe 4-8 cm long, 1-2 cm thick at the apex, equal or narrowed to a point at the base, solid; surface whitish, but soon bright yellow above, pallid downward, base dingy cinnamon, covered by pinkish-tan to vinaceous-brown glandular dots; no annulus; Context white inside at first but soon bright yellow within at apex, tinged cinnamon toward base.

Spore print dingy cinnamon to cinnamon. Spores 7-9 X 2.5-3.5 Ám, smooth, yellowish in KOH and Melzer's, subellipsoid, in side view somewhat inequilateral.

Basidia 18-24 X 5-6 Ám, four-spored, clavate, hyaline in KOH, merely yellowish in Melzer's. Hymenial cystidia 36-50 X 7-9 Ám, clavate to subcylindric, hyaline or with yellowish to brown content, in clusters with brown incrusted material around the base.

Tube trama of gelatinous divergent hyphae from a colored central strand. Pileus trama interwoven, homogeneous. Pileus cuticle an ixotrichodermium composed of hyphae 4-7 Ám wide, in KOH the contents dingy ochraceous to bister, some incrusting material present in the layer. Caulocystidia 40-70 X 7-10 Ám, clavate, subfusoid to cylindric, bases of clusters surrounded by brown pigment, contents hyaline to dark brown. Clamp connections absent.

Chemical reactions unknown.

Habit, habitat, and distribution Gregarious to scattered in humus under pines. This is truly a cosmopolitan species and has been found in most of the pine forests of the United States. It is common in the coastal forests of northern California and also occurs in the Cascade and Sierra Nevada ranges.

Material studied Madera County: Thiers 20859, 20955. Mendocino County: Thiers 8166, 8204, 8301, 8775, 8789, 8962, 8999, 9263, 9514, 9633, 10601, 11078. Mono County: Thiers 21000. Nevada County: Thiers 13157, 13249. Shasta County: Thiers 21595. Tuolumne County: Thiers 21066, 21092.

Observations This very common and well-known Suillus needs little comment. It is distinguished by the reddish brown color of the pileus, the absence of an annulus or even a ring of veil tissue on the margin of the pileus, the presence of conspicuous glands on the surface of the stipe, and a mild, pleasant taste. The absence of any type of veil is the major feature separating this species from both S. albidipes and S. glandulosipes. In the San Francisco Bay Area it has been confused with S. pungens, which, however, has a harsh, unpleasant taste and is typically white when young, becoming gray and finally rusty brown. Furthermore, young basidiocarps of S. pungens have a distinct cottony roll of veil tissue. Pantidou, in comparing pure cultures of the two species, has likewise found them to be highly distinct.

Edible and commonly eaten in many areas of the United States.

The Boletes of California
Copyright © 1975 by Dr. Harry D. Thiers
Additional content for the online edition © 1998 by Michael Wood, Fred Stevens, & Michael Boom
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