Pasture yield responses to phosphorus (P), sulphur (S), and potassium (K) were measured over four to eight years on different yellow#x2010;grey earth (pallic) soils at three non#x2010;irrigated (Timaru, Kauru, and Claremont soils) and one irrigated (Otiake soil) sites in North Otago. Large pasture yield responses to P at application rates up to 80 kg ha#x2212;1yr#x2212;1occurred on three sites with initial soil Olsen P levels of 6#x2013;11 #x3BC;g ml#x2212;1, but only a small response up to this rate was measured on the Timaru soil with a higher initial soil Olsen P level (16 #x3BC;g ml#x2212;1). The relationship between soil Olsen P and relative annual pasture yield was similar and moderate (r2= 0.57) for the average of the three most responsive sites. The highest pasture yield response to S was measured at application rates up to 80 kg ha#x2212;1yr#x2212;1on an Otiake soil with an initial soil sulphate S level of 3 #x3BC;g g#x2212;1. Smaller pasture yield responses at rates up to 40 kg S ha#x2212;1yr#x2212;1occurred on Kauru and Timaru soils with initial soil sulphate S levels of 8 and 4 #x3BC;g g#x2212;1, respectively. In four of the eight years there was a pasture yield response up to 10 kg S ha#x2212;1yr#x2212;1on the Claremont soil with an initial soil sulphate S level of 9 #x3BC;g g#x2212;1.
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