Increasing the Protein Content of Pasture Grasses by Frequent Light Applications of Nitrogen 1

There are many instances cited in literature of increasing protein content of various crops by applying nitrogenous fertilizers (~, 2, 3, 4, x3). 3 There are other instances of increased protein in grasses from association with legumes (5, 6) and from the growing of crops soils high in nitrate (7, ~2). In many cases the protein content pasture flora has been increased by top-dressings of fertilizers, containing phosphate, lime, or potash (8, 9), mainly by the increased cover of various legumes. On much of the cut-over land of Florida, however, and in particular the higher sandy lands, pasture legumes do not flourish, even when these elements are supplied. Protein content has also been increased by frequent mowing of pasture grasses (~4). The value of frequent top dressings of nitrogenous fertilizers for increasing the carrying capacity of pasture grasses has been shown (xo). It has been demonstrated at the Florida Experiment Station and on many farms throughout the state that certain improved pasture grasses make excellent growth throughout a considerable portion of the year. Grasses grown on soils with a low nitrogen content, however, generally contain low percentages of nitrogen, as can be noted from analyses given below. Any increase in protein content which may be made by fertilizing pasture grasses should make a better balanced feed, requiring less high-priced protein supplements for grazing dairy cows and fattening beef cattle. Preliminary work in ~927 indicated that grass top-dressed with sulfate of ammonia not only produced a much greater amount of forage when mowed frequently than when not treated with the nitrogen fertilizer, but the clippings contained a higher percentage of total nitrogen.