Effect of lime and form of superphosphate on productivity of dryland pastures

Abstract The effect of initial high lime (7500 kg ha‐1), annual low lime (200 kg ha‐1 yr−1), and no lime (all with 200 kg ha−1 yr−1 superphosphate) and dicalcic superphosphate (400 kg ha−1 yr−1) was compared over six years under sheep grazing and mowing on a low rainfall (800 mm), low pH (5.4), phosphorus (P) responsive (Olsen P 5) Matapiro yellow‐grey earth (Duric palic) soil near Hastings, Hawke's Bay, New Zealand. High lime significantly increased pasture dry matter yield compared with other treatments in the first three years of the trial under both grazing and mowing. There were no differences in annual yield between the other treatments. The response to high lime in relation to no lime in the first 3 years was greater under grazing (21%) than mowing (12%). There was a greater number of legume plants per m2 under mowing than grazing. The increase in pasture yield from high lime in the grazing trial was because of an increase in grass rather than legume yield. Legume yield averaged over all years was ...