ALFALFA 135 



in good form will also grow alfalfa in good form. 

 This does not necessarily follow. While there is 

 much of similarity in the soils suitable for the 

 growth of both, alfalfa may fail on lands that grow 

 red clover luxuriantly until the bacteria proper to 

 alfalfa have been introduced. Soils may be tested 

 for bacteria, and even in winter, by sowing some 

 seed in pots and treating them like well-cared-for 

 house plants. When the plants are 2 to 3 months 

 old, if tubercles are found on the roots, the conclu- 

 sion would seem safe that such soil does not require 

 inoculation. 



Place in the Rotation. — In a certain sense it 

 can scarcely be said of alfalfa that it is a rotation 

 plant, because of the long term of years for which it 

 is grown in an unbroken succession. Nevertheless, 

 in all places it cannot always be maintained for a 

 long term of successive years without renewal. In 

 the Eastern States it is frequently, though not al- 

 ways so crowded by various grasses, that the fields 

 in which it grows are broken up at some period 

 short of ten years, and not infrequently at the end of 

 five or six years. When thus grown, it becomes a 

 rotation plant, though grown in what may be termed 

 long rotations. But even in the West, where, under 

 irrigation, it may be grown for a quarter of a cen- 

 tury or even for a longer period without renewal, 

 it may be used when desired in short rotations. In 

 such situations it grows so readily and becomes es- 

 tablished so quickly, that the fields may be broken 

 with a view to alternate with other crops at the end 

 of the second year, or of any year subsequently from 



