Deep woods. Rare. New England, Frost.
This is apparently too closely related to B. chrysenteron, and it also resembles B. bicolor. Peck, Boleti of the U.S.
B. frater´nus Pk. Pileus convex, becoming plane or depressed, slightly tomentose, deep red when young, becoming dull red with age. Flesh yellow, slowly changing to greenish-blue where wounded. Tubes rather long, becoming ventricose, slightly depressed about the stem, their walls sometimes slightly decurrent, the mouths large, angular or irregular, sometimes compound, bright yellow, quickly changing to blue where wounded. Stem short, cespitose, often irregular, solid, subtomentose, slightly velvety at the base, pale reddish-yellow, paler above and below, yellow within, quickly changing to dark green where wounded. Spores 12.5×6µ.
Pileus 1–1.5 in. broad. Stem 1–1.5 in. long, 3–6 lines thick.
Shaded streets. Auburn, Alabama. July. Underwood.
The species is apparently allied to B. rubeus, but is very distinct by its small size, cespitose habit, color of the flesh of the stem and by the peculiar hues assumed where wounded. When the pileus cracks the chinks become yellow as in B. subtomentosus. The species belongs to the tribe Subtomentosi. Peck, Bull. Torrey Bot. Club, Vol. 24, No. 3.
B. subtomento´sus L.—sub; tomentosus, downy. Pileus convex or nearly plane, soft, dry, villoso-tomentose, subolivaceous, concolorous beneath the cuticle, often cracked in areas. Flesh white or pallid. Tubes adnate or somewhat depressed around the stem, yellow, their mouths large, angular. Stem stout, somewhat ribbed-sulcate, scabrous or scurfy with minute dots. Spores 10–12.5×4–5µ.
Pileus 1–4 in. broad. Stem 1–2.5 in. long, 2–5 lines thick.
Common and variable. The pileus is usually olivaceous or yellowish-brown, but it may be reddish-brown or tawny-red. When it cracks the chinks become yellow. The species, as I understand it, may be distinguished from its near relative, B. chrysenteron, by its paler flesh, the clearer yellow tubes not changing to blue where wounded, and by the chinks of the pileus becoming yellow. The species is recorded edible by Cordier, Curtis and Palmer. Gillet says it is only medium in quality. Peck, Boleti of the U.S.
Found and eaten in West Virginia, North Carolina, New Jersey, Pennsylvania. Specimens received from Indiana, Minnesota, Alabama. I have not seen any change of color in flesh or tubes. It is common in Woodland Cemetery and Fairmount Park, Philadelphia. If the tubes are not removed the dish is slimy. The B. chrysenteron also makes such a dish when stewed, but fried, and well done, both species are decidedly good.