The behaviour of the nitrification inhibitor “n‐serve” in broadcast and incorporated applications to soil

N‐Serve rapidly evaporated from coated fertiliser crystals scattered on glass plates or on soil. In the field in May more than 80% of N‐Serve in a broadcast application volatilised overnight and no inhibition of nitrification was observed. Vapour loss from coated fertiliser incorporated 3 cm deep in soil was negligible and nitrification was inhibited for at least 9 weeks. The half‐life of N‐Serve was 28 days in a soil low in organic matter and 50 days in a soil high in organic matter. Movement of ammonium nitrogen and N‐Serve over short distances in soil was observed but leaching of N‐Serve more than 2 cm below the depth of incorporation was slight. Much N‐Serve was lost whilst coating fertiliser, particularly when using a rotary evaporator. Analysis of treated fertiliser for N‐Serve is necessary for reliable estimates of inhibitor concentration.