When either ammonium sulfate or elemental sulfur is applied to provide the sulfur needs of a crop – with the nitrogen supplied by ammonium sulfate or other ammonium nitrogen fertilizers such as anhydrous ammonia, urea, or ammonium nitrate – the bulk of the acidity comes from conversion of ammonium to nitrate. Based on the normally applied sulfur rate of up to 30 kilogramsof sulfur per hectare, the use of ammonium sulfate versus elemental sulfur generates relatively insignificant soil acidification. The difference between the two sulfur sources is negligible relative to acidification generated from ammonium nitrogen sources typically applied at a rate of 100 to 200 kilograms of nitrogen per hectare on cereal crops.