About this fungus
Ash-tree Bolete is a fungus in the Boletinellaceae family. Its habitat and field characteristics are summarised below.
A yellow-brown to dark brown bolete with a flattened, often irregular cap and a short stem that may sit well off centre. The underside has unusually large, radiating pores that can look almost like gills.
What to check
Turn the cap over and look for elongated yellow to olive pores arranged in radial lines, with obvious cross-veins between them. Check for the short, eccentric or lateral stem and an ash tree nearby. Blue-green bruising may occur but is variable, so its absence does not rule the species out.
Lookalikes
Other boletes can share its brown cap, but most have smaller, more rounded pores and a central stem. The combination of coarse radiating pores, an off-centre stem and growth near ash is much more useful than cap colour alone.
Habitat and range
A North American species found on the ground close to ash trees. Its ecology is unusual: the fungus forms structures around colonies of root-feeding ash aphids and receives sugary secretions from them. It is therefore not well described as an ordinary tree-root mycorrhizal bolete.
Food safety
Edible.
Use this profile to learn what to examine and compare, not as proof that a mushroom is safe to eat. Check the whole specimen and every important lookalike before reaching an identification.
Photographs
Eshko Timiou / CC BY-SA 4.0