No. 4.] GRASSES AND FORAGE CROPS. 



203 



any of the nitrogen plots except where 75 pounds of nitro- 

 gen per acre were used. This would seem to indicate that 

 the effect of nitrogen in the fertilizer on the percentage of 

 protein in the crop is not nearly as marked with the legumes 



as with the grasses and cereals. 



Effect <>f NUrogenow Fertilizers on the Percentage of Protein in 

 Mi. nil Grasses, Oat Straw, Stover and Cow-pea Fodder. 



KIND OF FERTILIZER. 



Kind of Crop. 



Mixed 



Grasses, 



Proteiu 



(FerCent). 



Oat 



Straw, 



Protein 



(PerCent). 



Corn 



Stover, 



Protein 



(PerCent). 



Cow-pea 



Fodder, 



Protein 



(Per Cent). 



No fertilizer 



Mineral fertilizer 



Mineral fertilizer + nitrogen, 25 pounds 



per acre. 

 Mineral fertilizer + nitrogen, 50 pounds 



per acre. 

 Mineral fertilizer + nitrogen, 7"> pounds 



per acre. 



7.29 

 7.82 

 7.75 

 8.46 

 9.40 



7.39 

 5.04 

 4.89 

 5.25 

 6.02 



6.91 

 5.15 

 5.52 

 5.62 

 6.79 



18.64 

 18.25 

 18.19 

 17.75 

 19.55 



The relative effect of nitrogen upon the yields per acre 

 of dry matter and protein in the mixed grasses is shown in 

 the following table, and for comparison another table is 

 given, showing the relative effects on corn and stover. In 

 these tables the plots having corresponding amounts of 

 nitrogen have been combined, whether this nitrogen was 

 from nitrate of soda, sulphate of ammonia or dried blood. 

 In the case of the mixed grasses there was an increase of 

 about 1,000 pounds of dry matter for every 25 pounds of 

 nitrogen used. The percentage of increase obtained on the 

 nitrogen plots over the mineral plots shows that the relative 

 gains in protein were much larger than for the dry matter. 

 This indicates that the protein was increased relatively 

 faster than the other food constituents of the crop, and the 

 same is true for the corn and stover. 



