Alfalfa. 



225 



them are plats on which no nodules were found. In Bulletin No. 71, 

 Bureau of Plant Industry, " Soil Inoculation for Legumes," p. 36, Dr. 

 ]\Ioore states that sometimes hioculation takes place zoitluji the roots, 

 producing the usual benefit to the plant but no nodules being formed. 

 Possibly the two cases just mentioned are of this character. Both of 



Fig. 85. — Tlte eight plants at the left were grown from culture-treated seed, those on 



the right from untreated seed. 



these cases came under the writer's personal observation and there is 

 certainly no question but that the plants grown from the treated seed 

 were more vigorous than the others and many plants were examined 

 without finding a single nodule. No means were at hand for detecting 

 the presence of alfalfa bacteria within the roots. 



15 



