CHEMICAL COMPOSITION OF FEEDING STUFFS 57 
The results show a decrease in the percentage of water and, 
therefore, in the succulence of the crop. In order to show the 
changes in chemical composition, the analyses have been calculated 
to water-free substance, and it is seen that as the plant matures the 
percentages of ash, crude protein, amides, and fat decrease; as 
the stems grow hard and woody, the fiber contents of the plant in- 
crease, and the percentages of valuable feed components decrease in 
proportion, except that of nitrogen-free extract, which does not 
change materially. If we now consider the digestibility of the dif- 
ferent cuttings of alfalfa, we have the following average figures 
obtained in digestion experiments conducted at Ontario Rapicals 
tural Coliege: ? 
Digestion Coefficients for Alfalfa 
é Nitrogen- | 
D Crude... . 
matier | protein | Fat | free | Fiber 
First cutting............ 59 73 49 72 39 
Second cutting.......... 56 73 50 | 70 38 
Third cutting........... 51 64 44 64 37 
There is a decided decrease in the digestibility of the total dry 
matter and of all components as the plant approaches maturity ; the 
decrease is especially marked between the second and third cuttings, 
If the total digestible matter obtained in the three crops be calcu- 
lated on the basis of the figures just given, it will be found that 
the amounts of digestible matter secured in the later cuttings are 
considerably lower than those found in the earlier ones. In the 
Canadian experiments referred to, the three cuttings gave, on the 
average, the amounts of green alfalfa and digestible matter shown 
in the table: 
Calculated Yields of Dry Matter and Digestible Matter of Green 
Alfalfa Per Acre in Pounds 
Green Total dry | Digestible 
alfalfa matter matter 
; ; eh 
First cutting............ . 14075 2714 1590 
Second cutting......... 14513 3525 1978 
Third cutting........... 12363 3142 1611 
There was a decrease of 18.8 per cent, or nearly one-fifth, of the 
digestible matter during the two weeks’ interval between the last 
two cuttings, calculated on the yields of the second cutting. 
7 Report, 1899, p. 37, 
