207 



was able to obtain do more of its nitrogen from the soil than 

 was rye; this assumption that rye can draw from the soil at 

 least as much nitrogen as hairy vetch seems plausible, in 

 view of the well known strong foraging habits of rye, as evi- 

 denced in its successful growth on poor soil. 



If this assumption is correct, inoculated vetch plants 

 have obtained practically three-fourths (105.5— 26 = 79. 5- 

 pounds per acre) of their nitrogen from, the air. 



These figures seem to afford a rough measure of the fer- 

 tilizing or renovating value of leguminous plants. 



Of the total nitrogen in the entire plants the roots and 

 stubble contained 19 per cent, in the case of inoculated vetch, 

 16 per cent, with inoculated crimson clover, and 35 per cect. 

 with nearly mature rye. In all cases the stubble was shorter 

 than the mower would leave it, being only about 2 inches 

 long in the samples analyzed. It is doubtless safe to conclude 

 that with stubble of ordinary length fully one-fifth, and pos- 

 sibly one-fourth, of the total nitrogen would be left in the 

 soil after cutting the hay. 



With short stubble there was left on the soil in the roots 

 and stubble of vetch about four fifths as much nitrogen as 

 was afforded by plowing under the rye plants entire. In 

 longer or ordinary stubble and in its roots vetch doubtless 

 supplied as much nitrogen as both tops and roots of nearly 

 mature rye. 



Fertilizer Experiment With Hairy Vetch. 



Three of the one twelfth-acre plots in the field sown 

 with hairy vetch November 4, 1897, were used to ascertain the 

 relative profits of fertilizers applied at two different rates. 

 The land was sandy upland, hberally fertilized in recent years 

 with commercial fertilizers. 



Seed of hairy vetch, inoculated with Nitragin, was sown 

 broadcast November 4, at the rate of 30 quarts per acre. The 

 seed was worked in with a cultivator ; the fertilizers were then 

 spread broadcast and harrowed in. 



Acid phosphate at the rate of 240 pounds per acre, to- 

 gether with muriate of potash at the rate of 40 pounds per 



