 Hydnellum fungi are mycorrhizal , and are usually found in coniferous and mixed woods . Favored tree hosts include members of the Fagaceae and the Pinaceae . The genus is widely distributed in the Northern Hemisphere , particularly Europe and North America , but some species are found in the tropical Asia . Harrison identified a dozen new species from North America in the 1960s . Rudolph Arnold Maas Geesteranus recognized European 16 species in his 1975 treatment of the genus . 
