296 EXPERIMENT STATION— BULLETINS. 



NO. 49.-DEPAKTMENT OF CHEMISTKY. 



Chemical Composition of — 



1. Cornstalks and Ensilage at Different Periods of Growth. 



2. Marsh Hay from Paw Paw. 



3. Wheat Screenings from Kalamazoo. 



CORNSTALKS AND ENSILAGE. 



The chemical composition of cornstalks at different periods of growth, 

 and of the ensilage made from the same, has been a matter of inquiry by 

 intelligent farmers and stockmen, in order to fix upon the time for cutting 

 fodder corn to secure the best results. The following investigation has been 

 made as a contribution to this subject, and, while the results are not as 

 decisive as could be desired, it is hoped they will be of some value in settling 

 this question. 



Fodder plants at earlier periods of growth have greater food value, pound 

 for pound of dry matter, than the same plants at complete maturity, because, 

 in ripening, a part of the carbhydrates pass into indigestible condition as 

 woody fibre. But the total food value produced on an acre greatly increases 

 with advanced growth, from the rapid increase of digestible material along 

 with this increase of woody fibre. 



The acreage food value of a fodder crop will be at its maximum when 

 there is the largest amount of digestible albuminoids and carbhydrates, and 

 the least relative amount of indigestible fibre. The percentage chemical 

 composition, therefore, will have to be interpreted with reference to this 

 acreage increase of the crop. 



The food value may be computed in three ways : 



1. By chemical composition. 



2. By digestion experiments. 



3. By feeding stock. 



The last method would seem to be the most natural and decisive. There 

 are two objections to it. First, a number of animals must be fed in order to 

 eliminate the personal differences in feeding quality in different animals. 

 Second, animals require a change of food, and will not thrive if confined to 

 one kind of food for some time. 



A combination of chemical analysis and digestion experiments promises 

 the best results. The work this year has been mainly devoted to the chem- 

 ical analysis. 



The plan adopted was to gather a specimen of corn as soon as it tasseled, 

 make a chemical analysis of a part, and place the balance in a silo for future 

 analysis, and repeat this process every week until the corn was fully ripe. 

 In practice, however, the fresh stalks were examined for the amount of water 



