Sum16-29 Nitrogen and Phosphorus on Pasture, Darkan


To assess the most efficient way to allocate pasture fertiliser spend following a medium term cropping phase

For further details contact your local Area Manager or the Summit Research Team

Table 1: Soil Analysis
Fig 1: Total Dry Matter Produced
Fig 2: Dry matter response to N & P


  • Under these conditions for pasture grown directly after a medium term cropping phase, 65 $/ha spent on nitrogen generated the highest dry matter and returns.
  • For the most profitable N application, a balance between application when the requirement for extra feed is greatest and when growth conditions are more favourable need to be weighed against each other.
  • Lower response efficiencies during winter when soils are cold and wet may be offset by the increased value of the feed generated.
  • The results reaffirm that in a pasture situation, higher rates of Nirogen over smaller areas are likely to have a greater overall impact than low rates over a larger area