Sugar and acid values for 37 lots of silage made in 1951 and sugar values for the original green crops (plus preservatives or conditioners) from which the silages were made are summarized and reported. Variations in the values for the several lots are discussed, and possible explanations are offered. Of most interest are the apparently quite different type of fermentation that took place in the silage when SO2 was used as a preservative and the marked difference in amts. of the different organic acids, especially lactic acid, in grass silages as compared with legume silages. In most cases, sugar equivalent in the silage in the form of the aliphatic acids (acetic, butyric, and lactic) was much above what could be accounted for by the sugar content of the freshly ensiled crop. Considerable amts. of residual sugar were present in almost all the lots of silage when they were sampled and fed out.