> Stem not reticulate, or merely faintly so at apex. (1/2)

Page Five

> Stem distinctly reticulate, or coarsely reticulate to shaggy. (2/2)

° Found west of the Rocky Mountains, excluding Texas. (1/2)

~ Stem not predominantly yellow overall (though yellow may occur at apex or in combination with other colors). (1/2)

* Stem red to carmine red, with whitish to pinkish reticulation. (1/2)

Boletus frustosus

* Not as above. (2/2)

Cap pale pinkish to pink. (1/2)

Boletus pulchriceps

Cap olive to brownish or reddish brown. (2/2)

Xerocomus ferrugineus

~ Stem predominantly yellow overall. (2/2)

* Cut flesh instantly and consistently turning to blue. (1/2)

Stem without red colorations, but with olive-brown to black shades near the base. (1/3)

Boletus coniferarum

Stem covered on upper two-thirds (or more) with red reticulation. (2/3)

Boletus haematinus

Stem with reddish tints near the base, covered on upper half (or more) with yellow reticulation. (2/3)

Boletus regius

* Cut flesh not turning to blue, or doing so only slowly and/or erratically. (2/2)

Stem strongly reticulate with yellow reticulation, with a reddish base; cap surface macrochemical reactions unknown. (1/5)

Boletus abieticola

Stem with reddish brown stains, especially near the base, and inconspicuous yellow reticulation on upper portion; cap surface macrochemical reactions unknown. (2/5)

Boletus appendiculatus
At MykoWeb

Stem coarsely and deeply reticulate, with red areas near the base, reticulation becoming rusty red; cap surface macrochemical reactions unknown. (3/5)

Boletus holoxanthus

Stem without red shades, sometimes with brown stains, often whitish and narrowed at base; cap flashing green, then turning reddish brown with ammonia. (4/5)

Xerocomus ferrugineus

Stem with reddish brown streaks; only partially reticulate, at the apex; stem staining brownish to reddish brown when handled; cap instantly reddish brown with ammonia. (5/5)

Xerocomus subtomentosus

° Found east of the Rocky Mountains, or in Texas. (2/2)

~ Exposed flesh not turning blue when sliced and exposed, or only bluing slightly and erratically. (1/2)

* Pore surface yellow when young but soon becoming red, then orange red. (1/2)

Boletus carminiporus

* Not as above. (2/2)

Stem yellow above, pink to reddish below; cap surface green, then olive with ammonia; flesh bright yellow, then gray with ammonia. (1/7)

Boletus pallidoroseus

Stem yellow above, rosy red or darker red below; cap surface yellowish or red, then olive with ammonia; flesh yellowish (greenish blue near tubes) with ammonia. (2/7)

Boletus peckii

Stem golden yellow above, pale yellow but dotted or streaked burgundy red below; cap surface yellowish with ammonia; flesh dark yellow with ammonia. (3/7)

Boletus rufomaculatus

Stem yellowish or brownish but without red shades; cap surface showing a green flash, then reddish brown with ammonia; flesh reaction with ammonia unknown. (4/7)

Xerocomus ferrugineus

Stem rusty cinnamon to brown; cap surface "bluish green, then bright orange surrounded by dull grayish green, then entirely yellow orange" (Bessette, 2000) with ammonia; flesh negative with ammonia. (5/7)

Boletus subcaerulescens

Stem mostly yellow, with reddish brown streaks; cap surface instantly reddish brown with ammonia; flesh reaction with ammonia unknown. (6/7)

Xerocomus subtomentosus

Stem whitish to yellowish, often with reddish areas or a reddish zone; cap pink with ammonia; widely distributed east of the Rockies. (7/7)

Butyriboletus brunneus

~ Exposed flesh rapidly and consistently turning blue when sliced and exposed. (2/2)

* Young cap, pore surface, and stem bright yellow; flesh dark red in the base of the stem. (1/3)

Boletus pseudosulphureus

* Cap whitish to grayish when young, darkening to pale brown; typically becoming cracked, with white showing in the cracks; cap margin inrolled well into maturity; stem less than 2 cm thick; cap surface and flesh negative with ammonia. (2/3)

Caloboletus inedulis

* Not as above. (3/3)

-- Taste mild, not distinctive. (1/2)

Cap brown to yellow brown; young cap margin even; pore surface dark yellow-brown with bright yellow near the margin. (1/6)

Boletus fagicola

Cap yellow brown; young cap margin with projecting sterile portion; pore surface yellow becoming olive yellow. (2/6)

Boletus luridellus

Cap dark red to purplish red; young cap margin with projecting sterile portion; pore surface bright yellow to golden. (3/6)

Boletus purpureorubellus

Cap rusty brown to pale brown, often with reddish spots; young cap margin with projecting sterile portion; pore surface yellow becoming olive yellow. (4/6)

Boletus rufomaculatus

Cap rosy red to pink, becoming pinkish brown; young cap margin even; pore surface yellow becoming olive yellow. (5/6)

Boletus speciosus

Cap brown, usually with tiny projecting sterile margin; pore surface "stuffed" and bright yellow young, becoming olive yellow. (6/6)

Butyriboletus brunneus

-- Taste bitter or sour. (2/2)

Cap olive brown to dark yellow-brown; flesh yellow brown with ammonia. (1/3)

Boletus calopus

Cap olive brown to grayish tan; flesh olive green with ammonia. (2/3)

Boletus roseipes

Cap pinkish purple; flesh dull orange with ammonia. (3/3)

Boletus roseopurpureus

Cite this page as:

Kuo, M. (2003, June). Key to Boletus in North America (page four). Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/boletus_04.html

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