24 



BULLETIN 428, U. S. DEPARTMENT OF AGRICULTURE. 



far obtained. From an agronomic standpoint, groups 1 and 2 repre- 

 sent plants which in their pure state may be considered of value only 

 for pasturage on account of their procumbent tendencies, while 

 groups 3 and 4 are suiRciently erect to be utilized for the production 

 of hay. For convenience these groups may be referred to as pasture 

 and hay groups, respectively. 



BOTANICAL KELATIONSHIP. 



Considerable difference of opinion exists among botanists as to 

 the exact relationship which Medicago falcata bears to the group 

 of Medicagos commonly referred to as alfalfas. By many it is given 

 a specific rank coordinate with Medicago sativa. By others it is 









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Fig. 11. — Individual plant of Medicago falcata, S. P. I. No. 20726, a medium broad 

 crowned plant, decumbent to ascending in habit of growth, representing Group II. 



regarded as a subspecies of Medicago sativa, while some are of the 

 opinion that Medicago falcata is the true species and that Medicago 

 sativa is only a subspecies or a cultivated variety of it. Linnaeus 

 {38^ 39) at one time suggested the latter arrangement. 



Urban {62) divides Medicago sativa into two sections, '■''Macro- 

 car'pa'''' and '"''MicTOcaT'pa^'' and places Medicago falcata under the 

 former, coordinate with vulgaris, which he indicates is the common 

 cultivated variety of Medicago sativa. 



Alefeld {1) designates common alfalfa as Medicago sativa vulgaris 

 and Medicago falcata as Medicago sativa falcata. 



Ascherson and Graebner {2) follow essentially the classification 

 of Urban, but Rouy and Foucaud {51), Seringe {57), and many 



