EXPERIMENT STATION BULLETINS. 257 



plant food thus added to the soil is not readily washed out and the humus formed 

 from it besides supplying slowly needed plant food adds to the water-holding 

 capacity of the soil. What ppoportion of the nitrogen is lost in fermentation and 

 the subsequent changes into humus and finally into nitrate is not definitely 

 known and would depend upon many conditions. It is safe to asssume that 

 a large part of the nitrogen is lost, escaping as free nitrogen into the air. If 

 the soil is kept under good cultivation, if the soil particles are not too coarse 

 and if the amount of water present be regulated by drainage and cultivation, 

 the quantity of nitrogen so lost will be much reduced. 



To give the matter of the relative values of soy beans and cowpeas in building 

 up an exhausted soil, a plot 16 rods long 7 rods wide, which had borne sugar 

 beets for seven consecutive years was divided into three equal parts, each 

 4 by 7 rods in area. On one of these plots soy beans were sown in 1903, on 

 the next cowpeas and on the third buckwheat. In the fall it was found that the 

 roots of the cowpeas were fairly heavily loaded with nodules while the soy 

 beans had few. The green crops were plowed under and the whole area sown 

 to rye in the fall of 1903. 



In the spring of 1904 a strip 4 rods wide across al! three areas was plowed, 

 one rod planted to white beans, the next to field peas, the third to cowpeas 

 and fourth to soy beans, leaving the rye nominally 49.5 feet wide but really 

 45.25 feet. By this method soy beans followed soy beans, cowpeas, and buck- 

 wheat and it was possible to make a study of the influence of the previous 

 crop on that legume. The same thing was true of the cowpeas. 



The rye was cut July 15. Where following the soy beans the yield was 407 

 pounds; after the cowpeas it was 387 pounds and after the buckwheat 367 pounds, 

 the areas being equal, and 4 rods by 45.25 feet. The yield of grain was 134 

 pounds, following the soys, 115 pounds, following the cowpeas, and 119 pounds 

 following the buckwheat. Through the season it was noted that the rye was 

 slightly taller after the cowpeas; it was also slightly later in ripening on this 

 strip. 



The white beans occupied a strip a rod wide with equal areas on the plots 

 which had borne in 1903, the soy beans, cowpeas and buckwheat, the area on 

 each 1 rod by 4. The yields of straw and grain were as follows: 



Straw. Grain. 



After the soy beans 42 lbs. - 25 lbs. 



After the cowpeas 32 " 24 " 



After the buckwheat 32.5 " 25 " 



The field peas also occupied a strip 1 rod wide across the 3 plots. The yields 

 ■were: 



Straw. Grain. 



After soy beans 82.5 lbs. 27 lbs. 



After cowpeas 78.5 " 30 " 



After buckwheat 72 5 " 25 " 



Of the cowpeas, also 1 rod wide, the weights, green alone, were taken. The 

 yields were 90 pounds after the soy beans; 99 pounds after the cowpeas and 

 91 pounds after the buckwheat. 



The yield of the soy beans were 273 pounds after soy beans; 227 pounds after 

 the cowpeas, and 231 pounds after the buckwheat. 



The soy beans and cowpeas gave greater yields when grown the second year 

 on the same area than when following each other. The rye had the highest yield 

 after soy beans, as did the white beans and field peas if straw and grain are 

 considered together. The field peas gave a greater yield of grain after the 

 cowpeas. Before any definite conclusions can be drawn the experiment must be 

 repeated. 



ENSILOING SOY BEANS. 



On the 15th of September, 1904, 13,590 pounds of soy beans, just harvested, were 

 put into a silo. 



Beginning in the last week of April, 1905, this silage was taken from the 

 silo and fed to the cows. The silage had a peculiar and unpleasant odor which 

 filled the whole dairy barn and was noticeable for many rods. The silage when 

 weighed out amounted to 11,285 pounds and had the following composition: 



33 



