The addition of 0.5 to 1.0% limestone at the time of ensiling has proven beneficial to fermentation and improvement of acceptability of the silage. Several effects of the addition of limestone to materials at the time of ensiling have been noted, the most significant being the improvement in the production of total and individual organic acids. The organic acid most significantly influenced is lactic. The addition of more than 0.5% limestone at the time of ensiling reduced the total titratable acid. The addition of limestone to the ensiling material increased pH with increased levels of limestone; however, it is generally recommended that pH not exceed 4.5 for the most desirable silage. If this is true, the data suggest that 1% limestone or less be added to the ensiling material. These data suggest that the treating of silage with 0.5 to 1.0% limestone has no effect on average daily gain of cattle fed the treated silage. Feed efficiency, however, was generally improved by adding up to 1% limestone at the time of ensiling. Digestion experiments with lambs showed that the addition of limestone had no effect on digestibility of organic matter, cellulose, protein or ether extract of wholeplant or ground-ear corn silages. Since most beef cattle rations require a supplemental source of calcium, it seems logical and perhaps worthwhile to add limestone to materials to be ensiled. The addition of 0.5 and 1.0% urea to corn material at the time of ensiling increased the dry matter loss, increased the gas production and increased the lactic acid content of the resulting silage. The addition of urea seemed to have no consistent effect on carotene content of the silage. The treating of silage with urea resulted in a six- to nine-fold increase in ammonia, and these same silages contained no urea at the times of analyses. The feeding of raw soybeans with urea-treated silage demonstrated that there was not sufficient urea present in the silage to have a detrimental effect on gain or well-being of steers in the feedlot. When both urea and limestone were added to the corn material at the time of ensiling, they appeared to have the same influence as when each was added separately. Since an increase in crude protein and calcium content are desired in a silage, the recommendation is generally that 0.5% urea and 0.5% limestone be added to corn material at the time of ensiling. If sweet sorghum material is being ensiled, perhaps 0.75% urea and 0.5% limestone should be added in order to produce a silage with a sufficiently high crude protein content. There appears to be no difference in average daily gain of cattle fed urea-treated silage or those fed silage with adequate protein. In most of the experiments reported, there was a slight increase in feed efficiency and daily gain in favor of the animals fed the urea-treated silage. This increased feed efficiency for the animals fed treated silage was about 5% above the non-treated controls. No benefits were obtained by feeding various amounts and kinds of protein supplements in addition to urea-treated-high-moisture-corn silage. The addition of cotton-seed meal to rolled urea-treated high grain milo silage showed no effect. Digestion experiments with lambs indicated that the crude fiber in the complete ensiled ration was more available than crude fiber in the ration composed of corn silage and cornurea at the time of feeding. The TDN contents were not different. Nitrogen retention data showed significantly less nitrogen was retained by lambs fed the complete ensiled ration than those fed corn silage plus a mixture of corn and urea.