Twenty-six biochemical tests were used to study cultures of basidiomycetes isolated from roots of fruit-trees and other plants. The results enabled isolates to be placed into one of sixteen groups. Three of these groups were identified as Collybia drucei, Corticium utriculicum and Heteroporus biennis by matching their biochemical reactions with those of isolates from fruiting bodies of these fungi. This suggests that the other groups might also correspond to species. The three named fungi are indigenous, the first two not having been recorded elsewhere. Thus, root infections by these fungi may have originated from the indigenous fungal flora. Isolates of C. utriculicum and Stereum purpureum which were indistinguishable in culture were also separated using biochemical tests.