The nitrate-nitrogen contents of herbage at the first cut of 1956, and at a first cut in 1957

Herbage samples from two replicates of the first cut of 1956, and from two replicates of a first cut taken in 1957 in the present experiment, were analysed for nitrate-N. The 1957 results are included here as illustrating the influence of season on nitrate-N accumulation, although data from that year have not been reported in the two papers of the present series. Attention has been limited to first cuts, as nitrate-N accumulation is normally greater the shorter the interval between, the application of nitrogen fertilizer and sampling, and in addition the spring flush of growth is usually conducive to high nitrate-N contents (ap Griffith, 1961).