140 STORRS AGRICUI.TURAL EXPERIMENT STATION. 



quite light but were much larger than where no fertilizers 

 were used. On the whole the yields were very irregular, a 

 condition that has been pointed out in the di.scussion of the re- 

 sults obtained with other crops, and which was probably due 

 to the wet season. The series of sections supplied with nitrate 

 of soda (plots 7, 8 and 9) gave considerably larger yields than 

 were obtained on the sections supplied with mineral fertilizers 

 only; there was no relation, however, between yields obtained 

 and amounts of nitrogen supplied. It is of interest to note that 

 the increase of yields resulting from the use of sulphate of 

 ammonia was smaller than that from nitrate of soda, and that 

 the yields decreased in quantity with the increase of sulphate 

 used. This condition was not noticed in the experiment of 

 1900, but it may perhaps be due this year to an increasing 

 acidity of the soil (as pointed out in the the corn experiments) 

 resulting from the residue of acid left in the soil where large 

 quantities of sulphate of ammonia were used. * 



The amounts of nitrogen in the fertilizer arid the total yields of 

 the crop.—T\\& effects of the nitrogen in the fertilizer on the 

 percentages and yields of dry matter and of protein are indi- 

 cated by the results in Table 72. As was the case in the corn 

 experiments, the highest percentages of protein in the soy 

 beans are from the crops on the section without fertilizers. 

 This is probably due to the presence of a considerable propor- 

 tion of immature or partially developed seed. The percentages 

 of protein in the crop from the section supplied with only min- 

 eral fertilizer were lower than in the crop where nitrogen sup- 

 plied in the form of nitrate of soda was used. This would 

 seem to indicate that the nitrogen influenced in some degree 

 the composition of the crop as regards protein. Where the 

 sulphate of ammonia was used as fertilizer, however, the per- 

 centages were lower than on one of the mineral plots, and in 

 some cases nearly as low as on the other. As was pointed out 

 in the case of the yields of crop, the nitrogen from sulphate of 

 ammonia seemed to have little effect on the composition of the 

 crop. In fact the percentages of protein, like the yields of crop, 

 are in inverse order to the amounts of sulphate of ammonia 

 used. The relative effects of nitrogen on the yields per acre 

 of dry matter and of protein may be seen by referring to the 



