X 



LEGUMINOUS FORAGE CROPS 



I. ALFALFA 



196. Relationships. Alfalfa or lucerne (Medicago sativa L.), 

 also known as purple medic to distinguish it from other species 

 of the genus, belongs to the same tribe (Trifolieae) as the 

 true clovers (Trifolium) and the sweet clovers (Mclilotus), 

 all being characterized by the three leaflets into which the 

 leaf is divided. A number of species of Medicago have been 

 either grown in America or tested by the experiment stations. 

 These are black medic (M. lupulina L.), bur clovers (M. denti- 

 culata Willd. and M. maculata Willd.), snail clover (M. tur- 

 binata Willd.), sand lucerne (M. media Pers.), and yellow 

 lucerne (M. falcata L.). The last two are sometimes considered 

 by botanists as varieties of alfalfa (M. sativa L.), but they 

 differ widely in agricultural value. The name alfalfa is Spanish, 

 al = the article the, and falfa = fazfasah (Arabic), meaning 

 "a certain plant used for fodder." The earlier Spanish form 

 was alfalfez. 



197. Roots. Alfalfa is characterized by its strong deep 

 growing tap root. The depth depends on the age, character 

 of the soil and the depth of the permanent water table. In 

 some instances roots will have reached the depth of five feet 

 in six months, while those of old plants have been known to 

 grow extraordinary depths. (130) The tap root is usually 

 under one-half inch in diameter just below the crown, and 

 grows without many secondary roots nearly to its end where 

 it divides into a few branched roots of about equal size. 



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