Yellow-cracked bolete

Appearance

The pale olive or tan cap is initially convex before flattening, and measures 4 to 10 cm or sometimes up to 18 cm in diameter with a velvety tan surface. Occasionally the cap slits revealing yellow flesh beneath. The skin of the cap is very hard to remove. The pores underneath the cap are yellow, and bruise blue or green before fading somewhat. The stipe lacks a ring and is up to 8 cm tall by 1–2 cm wide. The spore print is olive-brown. A drop of ammonium hydroxide on the cap instantly produces a mahogany red reaction, which distinguishes it from some other similar species of the genus. The flesh is white and has little taste or smell.

Naming

The rare European species ''Xerocomus silwoodensis'', described as new to science in 2007, is similar in appearance to ''X. subtomentosus''. It can be distinguished from the latter in the field by the darker reddish-brown tones of the cap and its preference for associating with ''Populus'' trees.

Distribution

''Xerocomus subtomentosus'' occurs in autumn in forests throughout Eurasia, North America and Australia and forming a mycorrhizal relationship with a wide range of hardwood and conifer trees. It has been recorded from the vicinity of Tangier in Morocco, growing under cork oak . It is associated with bilberry and other evergreen shrubs of the Ericaceae.

Habitat

''Xerocomus subtomentosus'' occurs in autumn in forests throughout Eurasia, North America and Australia and forming a mycorrhizal relationship with a wide range of hardwood and conifer trees. It has been recorded from the vicinity of Tangier in Morocco, growing under cork oak . It is associated with bilberry and other evergreen shrubs of the Ericaceae.