Boletus barrowsii Thiers and A.H. Sm.
white king bolete
Boletaceae
Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.
Introduction to the Macrofungi
white king bolete
Boletaceae
Species account author: Ian Gibson.
Extracted from Matchmaker: Mushrooms of the Pacific Northwest.
Introduction to the Macrofungi
Species Information
Summary:
Features include 1) whitish to grayish buff smooth cap with suede-like texture, 2) thick unchanging whitish flesh, 3) pores that are whitish when young and do not become blue when bruised, 4) whitish to buff stem that is reticulate at least on the upper part, and 5) mild taste. Trudell(4) comment, "Generally considered to occur only in the Southwest, there have been sporadic reports of it occurring in places such as Idaho and southern California, under trees other than ponderosa pine. In Seattle, a very similar mushroom is fairly common in late spring under oaks and species of Tilia [italicized], such as lindens and basswood. Although it was felt that this had to be a different species, preliminary DNA analysis suggests it is very close to B. barrowsii.".
Chemical Reactions:
flesh stains gray with application of FeSO4
Odor:
not distinctive (Bessette), pleasant (Phillips), mild or sometimes strong and unpleasant when dried, (Thiers), strong odor when drying (Trudell)
Taste:
not distinctive (Bessette), pleasant (Phillips)
Microscopic:
spores 13-15 x 4-5 microns, subfusoid [somewhat spindle-shaped] to subelliptic [somewhat elliptic], smooth, ochraceous, (Bessette), spores 13-15 x 4-5 microns, subfusoid to subelliptic, smooth, pale ochraceous in Melzer''s reagent and in KOH, thin-walled; basidia 4-spored, 25-34 x 8-11 microns, clavate; hymenial cystidia crowded on pores, scattered to numerous on sides of tubes, 37-50 x 5-9 microns, "cylindric to subclavate to obscurely fusoid-ventricose"; cap cuticle poorly differentiated as a cutis of appressed to slightly interwoven hyphae; no clamp connections, (Thiers)
Spore Deposit:
olive brown (Bessette), dark olive brown (Thiers)
Notes:
If both close taxa are included, B. barrowsii found at least in ID, CA, AZ, NM, CO, and Mexico, (Bessette). The University of Washington has collections from WA and NM. It was reported from BC (Redhead(5)), and there are collections from BC at the University of British Columbia and the Pacific Forestry Center.
EDIBILITY
yes, choice, (Bessette, Arora)
Habitat and Range
SIMILAR SPECIES
Boletus edulis can be similar when whitish, but B. edulis has a clearly differentiated, often viscid cap cuticle (skin), (Arora). Caloboletus marshii has a bitter taste, has pale yellow pores when young, and lacks reticulation on the stem, (Arora). C. marshii has a bitter taste and bluing flesh, and lacks the reticulate stem (Frank). See also SIMILAR section of Boletus subalpinus.Habitat
scattered or in groups under ponderosa pine, fir, spruce, and live oak, (Bessette), single or scattered to gregarious under hardwoods and conifers
Status Information
Synonyms
Synonyms and Alternate Names:
Fomitopsis pinicola (misapplied name)