[Nitrogen fixation productivity in the plant phyllosphere]

The dynamics of nitrogen fixation was studied in the phyllosphere of birch and timothy, and the productivity of the process within the vegetation period was determined on the basis of the study. The activity of nitrogen fixation was measured under natural conditions using the acetylene technique. A proportion is suggested which makes it possible to determine the actual activity of nitrogen fixation in the phyllosphere from the potential one. The productivity of nitrogen fixation was 7 and 10 kg of nitrogen per hectare per season for birch and timothy respectively.