Grains and field crops
The current recommendations for time of application of soild nitrogen fertilisers such as urea, ammonium nitrate and sulphate of ammonia are:
Zone A: These fertilisers should be applied as close to seeding as possible.
Zone B: As for zone A except on very sandy soils which are very prone to leaching, where application can be delayed 2-3 weeks.
Zone C: Applications should be delayed about 3 weeks after seeding.
Number of Pages
Mason, M G. (1969), Time of application of solid nitrogen fertilisers.. Department of Agriculture and Food, Western Australia, Perth. Report.