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unless the roots become noduled. Without the nodules 

 the young plants grow but three to six inches high, grad- 

 ually turn yellow and die. Natural inoculation is rare 

 except in regions where alfalfa is grown extensively or 

 where a few closely related plants have been growing, 

 including melilotus, bur clover and yellow trefoil. The 

 fact that the nodule germs of melilotus will inoculate al- 

 falfa was first proven by Hopkins. There is no positive 

 proof in the cases of bur clover and yellow trefoil, but field 

 observations leave little doubt as to their efficacy. 



The nodules of alfalfa are small, club-shaped when 

 simple, but often branched- to resemble fingers. Rarely 

 there are enough branches to form a globose mass. These 

 nodules are all on the smaller roots, and are nearly always 

 stripped off when a plant is pulled out of the ground. 



391. Rate of seeding. One pound of common alfalfa 

 contains about 220,000 seeds. Therefore, each pound of 

 alfalfa seed, if evenly sown on an acre of 43,560 square 

 feet, would average over five seeds to the square foot. 

 Alfalfa fields one year old rarely contain more than twenty 

 plants to the square foot and older fields usually have 

 less than ten. In the United States, the usual rate of 

 seeding alfalfa to the acre is twenty pounds in the West 

 and twenty-five to thirty pounds in the East. In Europe, 

 the rate is variously given as twenty-five to thirty-five 

 pounds to the acre. Fair stands of alfalfa have been 

 secured in the West with one pound of seed to the acre, 

 and good stands are not rarely obtained with five pounds 

 an acre. 



Westgate, on the basis of thorough inquiry into the 

 practice of the best growers, recommends twenty-four 

 to twenty-eight pounds an acre for the Atlantic and 

 Southern States ; twenty to twenty-four pounds for the 



