224 ALFALFA FARMING IN AMERICA, 



ing bacteria was seen in Christian County, Kentucky. 

 A field of good limestone soil was well enriched 

 and sown to alfalfa in the fall. A fine stand re- 

 sulted and I visited it the next spring, some time 

 early in May. The alfalfa was short, stunted, of yel- 

 low color, clearly destined to be a failure. Careful 

 search revealed no nodules on the roots. One bunch 

 of thrifty alfalfa was in the middle of the field, 

 another at one edge, near where had stood a negro's 

 cabin. I dug up these plants and found abundant 

 inoculation, the nodules being plentiful. I dug out 

 the soil around these spots and threw it over the 

 field. Eains distributed the bacteria still further, 

 so that in a year the whole field was inoculated and 

 yielded a heavy crop of hay, about six tons to the 

 acre. The land had been well limed. 



Vital Relation of Bacteria. — ^What is the vital re- 

 lation between bacteria and alfalfa? I make no 

 pretense to exact scientific knowledge on this ques- 

 tion. As near as I understand it the case is about 

 as follows: Alfalfa is a legume. All or nearly all 

 leguminous plants are aided in their growth by bac- 

 teria that associate themselves with the plants, living 

 on the roots or on the rootlets. With plants using 

 these bacteria existence without them is precarious 

 and often impossible. 



Securing Nitrogen. — The problem of fertility, of 

 production of plants, of crop yield is a curious one. 

 Some elements going to make up plants are mineral ; 

 these we find in the ash of plants. A large part is 

 water; this comes easily enough from the soil. A 



