The paper is focused upon detail production-ecological analysis of the total herb layer biomass (above-and belowground) in the various types of the soft floodplain forests on the Danube river. The basic results varied between 1 and 5.5 t.ha-1 according to the herb layer cover. At all forest types, aboveground biomass is essentially higher than the belowground one (2.52–3.11). The results are compared with other ones obtained from the Danube and Morava river alluvium.