Effect of canopy development on ammonia uptake and loss from sugarcane fields fertilised with urea

Green cane harvesting with trash retention and reduced tillage has the potential to improve soil structure, increase soil organic matter, cat ion exchange capacity and nutrient levels, conserve soil moisture, control weed growth and reduce soil loss erosion. Consequently the practice has gained acceptance rapidly in appropriate circumstances notably in North Queensland, Barbados and South Africa. This paper reports the results of additional experiments conducted in north Queensland in the spring of 1992 to determine the effect of canopy development on ammonia absorption and loss by a well-watered crop.