Sulfur is considered a secondary plant nutrient and if soils are deficient adding sulfur can improve forage production. However, overapplying sulfur with ammonium sulfate or in other fertilizers is costly and can have negative impacts on soil pH, animal performance, and animal health.
The sulfur requirement for cattle is estimated at 0.15% of the diet dry matter. However, sulfur levels above 0.35 to 0.5% can result in reduced absorption of other important minerals and have negative impacts on cattle growth and health. Checking sulfur levels in hay samples can be helpful to ensure sulfur is not being overapplied.