This section is from the book "Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc.", by George Francis Atkinson. Also available from Amazon: Studies of American Fungi: Mushrooms, Edible, Poisonous, Etc..
This species occurs in woods and open places, growing on the ground in wet weather. It occurs singly or clustered, sometimes two or three joined by their bases, but usually more scattered. It is usually found under or near pine trees. The plant is 3-6 cm. high, the cap 2-7 cm. broad, and the stem is 4-8 mm. in thickness. It is very slimy in wet weather, the cap is yellow, streaked or spotted with faint red, and the stem is covered with numerous brown or reddish brown dots.
The pileus is rounded, then convex, becoming nearly expanded and sometimes with an umbo. It is soft, very slimy or viscid when moist, yellow. When young the surface gluten is often mixed with loose threads, more abundant on the margin, and continuous with the veil, which can only be seen in the very young stage. As the pileus expands the margin is sometimes scaly from remnants of the veil and of loose hairs on the surface. The cap loses its bright color as it ages, and is then sometimes streaked or spotted with red. The tube surface is nearly plane, and the tubes join squarely against the stem. The tubes are rather large, angular, yellowish, becoming dull ochraceous. The stem is nearly equal, yellow, and covered with numerous brownish or reddish brown glandular dots. No ring is present.
This species grows in the same situations as the B. granulatus, sometimes both species are common over the same area. Figure 171 is from plants (No. 3991 C. U. herbarium) collected at Blowing Rock, N. C, September, 1899. The species is closely related to B.flavidus Fr., and according to some it is identical with it.
Boletus granulatus L. Edible. - This species is one of the very common and widely distributed ones. It grows in woods and open places on the ground. Like B. americanus, it is usually found under or near pines. It occurs during the summer and autumn, sometimes appearing very late in the season. The plants are 3-6 cm. high, the cap is 4-10 cm. broad, and the stem is 8-12 mm. in thickness. The plants usually are clustered, though not often very crowded.
Plate 6i, Figure 170
Boletus obsonium. Cap cinnamon to pink or hazel in color, slightly tomentose; stem white, then pale flesh color (natural size). Copyright.
The pileus is convex to nearly expanded, flat. When moist it is very viscid and reddish brown, paler and yellowish when it is dry, but very variable in color, pink, red, yellow, tawny, and brown shades. The flesh is pale yellow. The tubes are joined squarely to the stem, short, yellowish, and the edges of the tubes, that is, at the open end (often called the mouth), are dotted or granulated. The stem is dotted in the same way above. The spores in mass are pale yellow; singly they are spindle-shaped.
The species is edible, though some say it should be regarded with suspicion. Peck has tried it, and 1 have eaten it, but the viscid character of the plant did not make it a relish for me. There are several species closely related to the granulated Boletus. B. brevipes Pk., is one chiefly distinguished by the short stem, which entirely lacks the glandular dots. It grows in sandy soil, in pine groves and in woods.