Nitrogen fertiliser use in grazed pasture-based systems in New Zealand: a summary

Abstract

Nitrogen (N) is an essential nutrient for plant growth. In grazed pasture systems in New Zealand, N fertiliser is regularly applied to maintain high productivity of ryegrass (Lolium perenne L.)/white clover (Trifolium repens L.) pastures. Several decades of trials/research have established the scientific basis for N management and N fertiliser application in grass/clover pasture systems. However, despite, or perhaps because of the rich diversity of this work, it isn’t always easy to see the full picture of this research; the seminal research and sometimes more recent advances are not always easily discoverable. This paper therefore seeks to amalgamate and summarise some of the vast amount of research on N fertiliser use in grazed pasture systems undertaken in New Zealand over the last 50 years. It provides an overview of research, raising the awareness of key findings, and importantly providing a pathway for decision makers to find and access the research on N fertiliser use and management. It also assists in the identification of knowledge gaps for new avenues of enquiry that could improve the efficiency of N fertiliser use and reduce environmental impacts of N loss from grazed pasture systems.