RECENT WORK IN AGRICULTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY— AGROTECHNY. 



Chemical studies in making alfalfa silage, C. O. Swanson and E. L. Tague 

 (U. S. Dept. Agr., Jour. Agr. Research, 10 (1917), No. 6, pp. 275-2.02).— This 

 is a preliminary report of two series of experiments on chemical studies in the 

 making of alfalfa silage, carried out at the Kansas Experiment Station. The 

 first series of experiments, started in 1912 and continued for four years, was 

 carried out in quart milk bottles ; the second series, started in 1914 and con- 

 tinued in 1915, in 10-ton experimental silos. A portion of the work has been 

 referred to (E. S. R., 37. p. 671), and a complete report will be published later. 

 The conclusions drawn by the authors are based on the results obtained from 

 both series of experiments. 



It was found that silage could be made from alfalfa alone if absolute exclu- 

 sion of air and retention of carbon dioxid could be secured. These conditions 

 are, however, indicated as not practical of realization. The addition of sup- 

 plements was found to insure a more rapid and plentiful production of acids, 

 which makes conditions for putrefactive organisms unfavorable. Wilted al- 

 falfa was more suitable for silage than unwilted. The addition of water to 

 unwilted alfalfa was harmful, while no decisive results were obtained by the 

 addition of water to wilted alfalfa. 



Molasses was found to be the most effective supplement tried. Germinated 

 corn was more effective as a supplement to alfalfa than sound corn, the results 

 produced being similar to those produced by molasses. It is indicated that rye 

 would be a suitable supplement but for the strong odor which it imparts to the 

 silage. 



The value of tightness of packing lies only in the fact that it makes the ex- 

 clusion of air more certain. 



In good alfalfa silage about one-third of the nitrogen was found to be in the 

 amino form, while in bad silage the amount was sometimes one-half that of the 

 total nitrogen. 



" Most of the acids present in alfalfa silage are produced in the first two 

 v:eeks. The percentage of acidity may increase after that, but the increase is 

 comparatively slight. The alfalfa, as it is put into the silo, contains only a 

 small amount of nitrogen in amino form. Most of the change of nitrogen into 

 amino form takes place in the first 10 days. Silage from wilted alfalfa con- 

 tains more nitrogen in this form than that made from fresh alfalfa. Sugar 

 present in the materials used in making silage disappears very rapidly. Com- 

 pletely matured silage contains no sugar." 



The isolation of parahydroxybenzoic acid from soil, E. H. Walteks (Jour. 

 Amer. Chetn. Soc.. 39 {1911/), No. 8, pp. 1778-17-84) ■—A.n aromatic acid whose 

 identity with parahydroxybenzoic acid was established was isolated from a 



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