Table I. Yield of Oat and Pea Hay. 



Yield per Yield per Increase due 

 Plot. Acre Total, to Nitrate. 

 Pounds. Pounds. Pounds. 



Plot 



1 Minerals + 100 Ibs. Nitrate of Soda, 320 3,200 700 



2 +150 320 3,200 700 



3 only .................... 210 2,100 



4 + 200 Ibs. Nitrate of Soda, 385 3,850 1,350 



5 +250 460 4,600 2,100 



6 only .................... 290 2,900 ____ 



7 + 300 Ibs. Nitrate of Soda, 540 5,400 2,900 



8 +350 550 5,500 3,000 



Food for 

 Plants 



113 



It is very evident from a study of this table that 

 Nitrogen was essential in order that a larger crop might 

 be secured, for, although a reasonably liberal dressing 

 of minerals was applied upon the entire area, those plots 

 upon which no Nitrogen was applied showed a very 

 much lower yield than on any of the other plots, though 

 probably quite as high as is obtained on the average 

 from what is regarded in that section as fairly good hay 

 land. The increase, however, was very marked from 

 the addition of Nitrate, and is practically in proportion 

 to the amount added until a dressing of 300 pounds per 

 acre is reached. That is, it is shown that not only is 

 Nitrogen needed, but the conditions of soil and of season 

 were such as to enable the plant to utilize the Nitrogen 

 almost completely when as heavy a dressing as 300 

 pounds per acre was used, increasing the total tonnage 

 from 1J4 to nearly 2% per acre. 



A study of this utilization is interesting. Assuming 

 the average composition of Nitrate of Soda to be 15.5 

 per cent. Nitrogen, and taking the average content of 

 protein in oat and pea hay, which for even mixtures of 

 oats and peas is 10.31 per cent, equivalent to 1.65 per 

 cent. Nitrogen, we find the following results: 



Plot 



1 



2 

 4 

 5 



. 7 

 8 



Recovered in crop. 

 11.55 Ibs. 

 11.55 

 22.28 

 34.65 

 47.85 

 49.50 



