940 



EXPERIMENT STATION RECORD. 



the same as determined by actual diminution in weight of silage in experimental 

 silos. 



"These results as to temperature change, loss in weight, and gases evolved are only 

 explicable on the common hypothesis that the normal changes are due to . . . 

 direct and intramolecular respiration of the plant cells themselves; and that normally 

 . . . (bacteria and mold) only function in a detrimental way when air finds access 

 to the mass of plant tissues. ' ' 



In order to show the causal relation of plant-cell activity to silage formation, 

 immature cut corn placed in a receiver and immediately frozen to destroy the cell 

 activity, was compared with a sample ensiled in the usual way. One frozen sample 

 was treated with ether. After 22 days all samples were opened. Only the sample 

 treated in the usual way had a distinctly silage aroma, while the other samples had 

 a pronounced offensive odor suggestive of incipient putrefaction. A bacteriological 

 examination of the samples was made and the conclusion reached that if the silage 

 changes were attributable to bacteria the frozen corn should have made as good silage 

 as the other. Practically the same amount of acidity was found to have developed 

 in the frozen and the check samples as the result of bacterial growth, but in the 

 frozen .samples treated with ether the acidity was very much lower. From these 

 results it is concluded that owing to the immediate destruction of the life of the plant 

 cells the changes which characterize silage formation did not take place. 



A number of samples of the same lot of corn were ensiled and opened on different 

 dates to determine the relation of aroma production to death of plant cells. "The 

 production of the characteristic aroma at the early stages noted, before the plant cells 

 had dfed, is hardly compatible with the view that these changes are explicable on the 

 theory that they are caused by the jirowth of organisms that must develop on the 

 cells of the ensiled tissues. This observation adds probability to the conclusion 

 already drawn that the internal processes of the living plant cell are the factors that 

 inaugurate the series of changes that result in the production of typical silage." 



Influence of close packing- of corn in the silo on the unavoidable losses in 

 making- silage, F. H. King {}yiscotisin Sta. Jlpi. 1901, pp. 200-209, fig. 1). — This 

 experiment is the repetition of an investigation made the year before (E. S. R., 13, 

 p. 38). Well matured corn was ensiled in pint and quart bottles in such a way as to 

 have closely duplicate material in each bottle, but with more entangled air and looser 

 packing in the quart than in the pint bottles. Air was prevented fi-om entering the 

 bottles, but the evolved gases were permitted to escape. The weight of the corn 

 put into each bottle, together with the losses, are shown in the following table: 



Losses in the weight of material in the silo. 



The above figures show an average loss nearly 3 times as large with the loose pack- 

 ing as with the close packing. The closely packed pint bottles came to a constant 

 weight in 8 and 9 days, respectively, while the quart bottles continued to lose for 28 

 and 30 days. The periodicity in the loss of weight after the rate of change had 

 become small was evident in the data reported last year, and was again observed in 

 these experiments. 



The silos entering into the experiments of the previous year were left undisturbed, 



