King Bolete: Boletus edulis

Pileus
Cap 7-25 cm broad, broadly convex; surface smooth to wrinkled, dry to subviscid in wet weather; color varying from yellow-brown, buff-brown to reddish-brown; flesh thick, white, unchanging; odor and taste mild.

Hymenophore
Pores very small, pallid, becoming dull yellow, finally dingy yellowish-green.

Stipe
Stipe 7-20 cm long, 3-8 cm thick, equal to clavate, white at the base, brownish above; white reticulations especially at the apex; veil absent.

Spores
Spores 12-17 x 4-6 µm, smooth, fusiform to elliptical. Spore print olive-brown.

Habitat
In the California, Boletus edulis is associated primarily with pine, particularly Pinus muricata (Bishop pine), and Pinus radiata (Monterey pine). It fruits sporadically during the spring and summer months (in the latter case from fog drip), with significant fruitings occurring after the first soaking rains of autumn.

Edibility
Edible and choice. Buttons are usually prepared fresh while large specimens are typically dried. Like many members of the bolete group, fruiting bodies of Boletus edulis are frequently colonized with fly larva making it difficult sometimes to find edible specimens.

Comments
Boletus edulis is distinguished from other members of the bolete group by a combination of characters: substantial size, a smooth to wrinkled brown to reddish-brown cap surface, drab white pores becoming yellowish olive in age, a usually club-shape stipe with distinctive white reticulations at the apex, mild taste, and absence of color changes. A close relative is Boletus regineus (Queen bolete) which differs in having a darker cap with a whitish wash when young, and occurs with mixed hardwoods as opposed to pines.
Long known as Boletus edulis, our California taxa has recently been given a new varietal name: Boletus edulis var. grandedulis Arora & Simonini.