128 STORRS AGRICULTURAL EXPERIMENT STATION. 
marked differences were noticed in the growth on different plots 
till the latter part of July. | 
July 31st it was observed that the plots to which dissolved 
bone-black had been applied were making better growth than 
the other plots. This was noticeable on plots B, D and F. 
Later in the season the plots with potash took the lead. 
Asis usually the case with legumes, potash seemed to have the 
most marked influence on the yields. Plot C gave the heaviest 
growth of any of the plots with single fertilizers, while E with 
nitrogen and potash gave a considerably better growth than D 
with nitrogen and phosphoric acid. 
The increase from the use of nitrogen (nitrate of soda or 
manure) was not very marked, as may be seen by comparing the 
yields on F with only mineral fertilizers with that on G with a 
complete fertilizer, and on Y with manure and X with manure 
and dissolved bone-black. 
The percentage composition and the yield of the different nu- 
trients per acre are shown in table 37, on the opposite page. 
The influence of nitrogen on the composition of the crop of 
this experiment is quite interesting. Unlike the grasses, the 
legumes seem to be but little affected in their protein or nitrogen 
content by the addition of nitrogen in the fertilizers. Potash 
appeared to have the most marked influence over the percentage 
of protein in the crop. Plot C with potash alone, and Plot F 
with potash and phosphoric acid, gave the highest percentages of 
protein in the crop. | | 
Plot G with a complete fertilizer costing $12 per acre, yielded 
only 420 pounds per acre more than plot F, which had the same 
mineral fertilizers, but no nitrogen, and cost $8 per acre. The 
total protein on the two plots was very different from the total 
crop. Plot G, with nitrate of soda, yielded protein at the rate of 
496 pounds, while I’, without the nitrate, produced at the rate of 
534 pounds per acre. 
This experiment points out two reasons for not using nitrogen 
compounds to any considerable degree, in the fertilizers used in 
growing leguminous crops. The total yield is but little if any 
greater where nitrogen is used, and the protein in the crop does . 
not seem to be increased by its use. 


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