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PASTORAL AND AGRICULTURAL BOTANY 



Description. The alfalfa is a perennial member of the leguminous 

 family with deep growing roots penetrating usually to about nine feet, 

 but under exceptional conditions to a depth of forty and even sixty feet. 

 The aerial stems are ascending, or erect, and increase in number with 

 successive cuttings, so that a single root system may give rise to as many 

 as one hundred stems, although usually the number varies from twenty to 



Pic. 77. Alfalfa, or lucern (Medicago saliva): a, b, seed pod, side and end view: 

 c, seeds, enlarged. (After Smith, Jared G.: Meadows and Pastures. Farmers' Bulletin 

 66, 1904, p. 27.) 



fifty. Three cuttings are made yearly throughout the alfalfa-growing 

 regions of the United States, although in the Imperial Valley, California, 

 as many as nine cuttings have been made in one year. The leaves are 

 with a serrate margin (Fig. 7 7) . The inflorescence is a short, dense raceme 

 with purple, papilionaceous flowers. The color may at times be green, 

 blue or yellow. The calyx teeth are longer than the so called calyx tube. 

 The standard exceeds the wings,in length, which are longer than the keel. 



