Graslander Uitgawe 1: Nampo | Page 7

TEGNIES EFFICACY OF LAN COMPARED TO UREA UNDER DRY CONDITIONS FOR MAIZE Numerous research studies have shown higher yields (5% to 25%) for ammonium nitrate based products compared to urea over years and over many different localities. Most efficacy comparisons between these sources were done under high rainfall conditions conducive to volatilisation and leaching losses of nitrogen. Under relatively dry conditions toxicity and volatilisation effects of urea are expected when concentrated and when the soil is only moist. Research that was done previously at the ARC-GCI was revisited to investigate efficacy differences between Limestone Ammonium Nitrate (LAN) and urea for a specific season when particularly dry conditions occurred after planting. These N-sources were band placed at a depth of 10 cm, 10 to 15 cm from the rows, 3