The evolution of the release of nutrients from a snow cover may determine their availability for plants. In this study the nitrate release from a snow pack on an open field in Alptal was measured in winter 1998/1999. With the diminution of the nitrate concentration in single snow layers a hint for ionic fractionation has been found. The measurements allowed to estimate the variability of the water and nitrate release from the snow pack. Its high spatial and temporal heterogeneity is explained with preferential flow paths of the melt water.