Pasture responses to phosphorus and nitrogen fertilisers on east coast hill country: 2. Clover and grass production from easy slopes

摘要

Abstract From 2000 to 2002 a trial series was established on seven farms from Wairoa (northern Hawke's Bay) to Moeraki (North Otago), with contrasting amounts of spring‐summer rainfall, to evaluate the pattern of pasture responses to a range of rates of nitrogen (N) fertiliser and a range of soil phosphorus (P) levels. Small plots excluded from grazing were established on flat to gently sloping land containing pastures that had been established for many years. This paper describes the clover and grass component production responses to N fertiliser and to a range in soil P status at each site. In early spring, in all years, the grass components of pasture at all sites except Marlborough, showed a significant response in dry matter (DM) production to N fertiliser applied in mid winter. These responses continued into late spring‐autumn at most sites/ years. The consistency from year to year of the relative grass response in spring to N fertiliser allowed significant regression relationships to be developed f...