Kolorado-Tanne
"Boletus rex-veris" is found under pines ("Pinus ponderosa", "P. contorta" subsp. "murrayana") and firs ("Abies concolor" and "Abies" species) at elevations of . It is often buried under needle duff and fruits from May to June in California. In Oregon it fruits at lower elevations, and its range continues into Washington, Idaho, and British Columbia.