The actual diameters of fungal mycelium are shown to be significantly
lower and that of spores higher than the arbitrarily accepted diameter
of 5 mu m. A substantial similarity exists for the actual diameter of
fungal mycelium in two soils of the forest zone (4.1 and 4.0 mu m) an
d in two soils of the steppe zone (2.0 and 3.3 mu m). The length of fu
ngal mycelium was much greater in all soil types in the rainy summer o
f 1993 than in the relatively dry summer of 1992. Indicators of fungal
biomass, calculated with consideration of the actually established an
d tentative values of the diameters of spires and mycelium in Sod-Podz
olic soil practically did not differ, whereas in Chernozem and Chestnu
t soils, the differences reached a factor of 1.5-2.