162 MASS. EXPERIMENT STATION BULLETIN 154. 



seed showed no appreciable differences. The rates of yield 

 are shown in the following table : — 



It will be noted that in both experiments there was con- 

 siderable gain due, in so far as can be judged, to the use of 

 the culture. An examination of the roots at a number of 

 different points in the early spring of 1910 showed, however, 

 that there were nodules on the uninoculated as well as on the 

 other, and in both cases by the end of the season there was 

 no difference which could be detected by close observation 

 in the appearance of the inoculated and uninoculated plots. 



In 1911 the growth of the uninoculated was fully equal to 

 that of the inoculated, and the weights were not separately 

 taken. The value of the increase in the yield the first year, 

 supposedly due to the inoculation, was, however, much greater 

 than the cost of the culture (S2 for an acre) and the labor 

 entailed in using it. The conclusion appears, therefore, to be 

 justified that when alfalfa is put upon land on which the crop 

 has never been grown the use of a commercial culture is likely 

 to be profitable. 



The rates of yield per acre on these fields in succeeding 

 years are of interest in this connection. They show con- 

 clusively that on suitable soils rightly managed alfalfa is a 

 valuable crop. The yields are shown in the following table: — 



Field D 



(Tons 

 per Acre). 



North Field 



(Tons 



per Acre). 



1911, 

 1912, 

 1913, 



2.72 

 2.99 

 3.89 



2.80 

 3.58 

 4.97 



