PR - How Much Is A Kilogram Of Nitrogen Worth?

Economic information is important for Australian wheat growers when making fertiliser decisions, because urea and grain prices have been changing in recent years. Existing Australian approaches to developing fertiliser recommendations fail to account for economic factors. A new approach to making fertiliser decisions is illustrated in this paper, which accounts for the patterns of crop response as fertiliser is added, and for associated marginal benefits and costs. This decision framework develops information to find the best level of nitrogen fertility to meet the profit objective and allows growers to set a target rate of return that their nitrogen investments might be required to meet, while accounting for factors such as soil moisture at sowing and uncertain in-crop rainfall. It could be used in a new approach to providing decision support to wheat growers about making nitrogen decisions in the Australian cropping zone, and a proposal for further research is outlined.

Keywords: Farm management economics, nitrogen, fertiliser, wheat, decision support, Australia