IO6 RECLAIMING LOST NITROGEN. 
that they are better adapted to the legume. In either case, the 
second season will show a more luxuriant growth and a more suc- 
cessful nitrogen fixation. 
Soil Inoculations. Experience has shown that it is not always 
possible to get a good growth of the desired legume, because of the 
failure to obtain a proper quantity of tubercles. That this is due 
to the lack of the right variety of bacteria in the soil seems certain, 
and has led to the practice of inoculating the soil. The first method 
of doing this is to obtain soil from some locality where the legume is 
known to produce a goodly numbers of tubercles and then either to 
FIG. 27. Two snap-bean plants, growing in coal ashes, one with 
and one without inoculation (Ferguson). 
mix this soil with that of the field to be planted, or to make a soil infu- 
sion to be used for soaking the seeds or for watering the young plants. 
The results of this procedure are, in the main, satisfactory, for 
generally the production of tubercles is thus stimulated, and much 
increased crops produced (Fig. 27). In many instances of this 
kind it has been found possible to cultivate a legume in soils in which 
it would not previously grow, by simply inoculating the new soil 
with soil where the legume has previously grown. Alfalfa, for ex- 
ample, has been successfully started by this means in many 
places in the eastern part of this country where it would not pre- 
