187 



It was not suspected until recent years that any soils 

 stood in need of being artificially supplied with root-nodule 

 bacteria. Salfeld and others found that "moor soils," a small 

 and peculiar class of peaty soils found in Europe, were 

 benefited by artificial inoculation for certain legumes. 

 No account of large areas of American soils needing in- 

 oculation had been published so far as could be learned prior 

 to Bulletin 87 of this station. That bulletin pointed out the 

 fact that in many portions of Alabama the frequent failure of 

 clover, alfalfa, and other rarely grown legumes was due to 

 the absence or insufficiency of the corresponding root-nodule 

 bacteria in the soil. 



Since soil of an old clover field contains abundant clover 

 germs, since these are necessary to the abundant growth of 

 clover, and since they are wholly or in part absent from some 

 soils, it follows that soil from an old clover field should be 

 added to soils thus deficient and hence unsuitable for clover. 



Quite recently a German firm whose American agents 

 are Victor Koechl & Co., 79 Murray St., New York, have 

 placed on the market a preparation called Nitragin. The 

 several brands of Nitragin contain in concentrated form the 

 same kinds of germs that are found in old fields of clover, 

 vetch, alfalfa, etc. 



Either this prepared material or the soils containing the 

 requisite root-nodule bacteria may be used as an inoculating 

 material. Both have been separately used in our experiments 

 and both have been highly beneficial. 



Crimson Clovek and Hairy Vktch. 



Before describing in detail our experiments in which 

 there was an enormous increase in the yield of crimson clover 

 and hairy vetch, brief notes regarding these two plants are in 

 order. 



Crimson clover is an annual leguminous plant making its 

 growth between October and May. Making all of its growth 

 in the cooler, moister portion of the year, it escapes with less 

 injury than does red clover from dry weather in summer. It 

 has a head which is two or three times as long as that of red 



