7 
, Bae ‘ 
160 STORRS AGRICULTURAL EXPERIMENT STATION. 
The oats were sampled at the time of threshing and weigh- 
ing the crop, the sample of straw being taken as in sampling 
hay. Of the grain a sample of 2 to 6 pounds was taken imme- 
diately after the crop was weighed, and, after being partially 
dried, was finely ground and the samples stored in sealed jars 
until they could be analyzed. 
The cow peas were sampled just after the crop was cut for 
silage, in much the same way as the grasses, and the seed of the 
soy beans were sampled in about the same way as oats, just 
after the crop was thrashed and weighed. 
The analyses are published mainly to show the effect of 
nitrogen in the fertilizer on the proportion of nitrogen com- 
pounds (protein) in the crop. The chief point of interest in a 
study of them is found in a comparison of the protein in the 
crops from the plots to which only mineral fertilizers were ap- 
plied, with the protein in the crops from the plots to which 
nitrogen also was applied at the rate of 25, 50, and 75 pounds 
per acre. (Compare plots 6, 6a, 6b with plots 7, 8, 9, and Io, 
iy 12:) 
The data in the tables giving the yields of nutrients per acre 
were obtained as follows: The weight of the crop at harvest 
multiplied by the percentage of water-free substance in the 
crop, as shown by drying the small samples in hydrogen gas at 
100° C. (212° F.), gives as a product the total amounts of 
nutrients, or water-free substance, per acre. The amount of 
water-free substance multiplied by the percentages of nutrients 
contained in it, as shown by analysis, gives the yields of these 
ingredients per acre. 
Explanation of Tables 25 and 26.— The analyses given in 
Table 25 are those of samples of mixed grasses from experi- 
ments conducted by the Station during the years 1890, 1891, 
and 1892. The general plan of the experiment included a 
series of plots upon all of which, except the “ nothing ”’ plots, 
was applied uniform quantities of phosphoric acid and potash, 
and, in addition, different quantities of nitrogen. The nitrogen 
was applied upon three of the plots in nitrate of soda, and upon 
three others in sulphate of ammonia. The kinds and quanti- 
ties of the different fertilizers used are given in the second 
column of the tables. The third column shows the kind of the 
experiment. In determining the proportions of food constit- 
uents, 1. é., protein, fat, etc., in the crop, the differences in the 
proportions of water are left out of account by basing the cal- 
culations upon the amount of dry matter or water-free sub- 
stance in the crop. 


