E-Flora BC: Electronic Atlas of the Flora of British Columbia

Summary:
Features include 1) a nearly spherical fruitbody with the surface pallid becoming dingy brown without any red staining when handled, 2) a spore mass that is dark vinaceous-brown when fresh, 3) growth under conifers, 4) chemical characters, and 5) microscopic characters including smooth, truncate spores, and a peridium of appressed hyphae.

Rhizopogon columbianus has been found in BC (Smith(4)).

Outer Surface:
"about 2cm, pallid becoming dingy brown, then with a slight cinnamon tint", (Smith), up to about 2cm by 1.4cm, nearly spherical, slightly compressed; pallid when young but soon with dingy streaks over surface and gradually dingy brown with slight vinaceous tint, not changing color markedly on handling; "dry and unpolished, lacking conspicuous rhizomorphs", (Harrison)

Stem:
columella absent (Harrison)

Chemical Reactions:
slightly vinaceous on surface with KOH, with FeSO4 no reaction on surface, (Harrison)

Interior:
when fresh dark vinaceous-brown, when dried hard and olive-brown, (Smith), firm, hard, hard when dried; when mature deep vinaceous brown, when dried more olivaceous brown, (Harrison)

Odor:
not distinctive (Harrison)

Taste:
not distinctive (Harrison)

Microscopic:
spores 6.5-8 x 3-3.8 microns, truncate, pale cinnamon in KOH; "peridium of appressed hyphae 4-9 microns wide, cells short to long but none greatly inflated", "epicutis merely of appressed hyphae", (Smith), spores 6.5-8 x 3-3.8 microns, oval to elliptic (truncate at base), smooth, in Melzer''s reagent and in KOH groups are pale tawny to cinnamon (not dextrinoid), wall thin (to 0.25 microns); basidia "becoming thick-walled as do the basidioles"; subhymenium "cellular, the cells also finally with thickened walls"; tramal plates of narrow, interwoven, refractive-gelatinous hyphae; peridium of hyphae 4-9 microns wide, appressed, short to long but none greatly inflated, some brownish debris in the layer and some hyphae with incrustations but not with distinct color revived in KOH, epicutis "merely of appressed hyphae, not distinct as a layer", in Melzer''s reagent no pigment globules present and no distinct color reaction; clamp connections none but pseudoclamps rarely present, (Harrison)