Concern has been expressed during recent years that sulfur may have become more limiting for plant growth and subsequently ruminant animal nutrition than was expected. This likelihood is based largely on the fact that (a) the inherent sulfur content of fertilizer phosphates has greatly diminished with declining use of normal superphosphate in manufacture of mixed fertilizers, (b) increased regulatory effect on burning of high sulfur fuels, and (c) increased use of nitrogen fertilizers for production of animal feeds. Assumedly, any or all these factors could result in alteration of nitrogen and sulfur content of forages to the point that either growth of the crops or utilization of forages by ruminant animals could be affected. This situation is very important to Kentucky agriculture with its heavy dependence on forage crop production for support of its 2.5-3.0 million head of cattle and calves.
Appreciation is expressed to the Sulfur Institute for partial financial support of this project.
Wells, Kenneth L., "N:S Ratio of Forages in Kentucky" (1983). Agronomy Notes. 80.