LEGUMINOS^ 447 



the lowermost nodes and from the axils of the cotyledons. 

 The result is a well-developed "crown." 



Geographical. — Common alfalfa is a native of temperate western Asia. The 

 original home is probably from northern India to the Mediterranean region. 

 It is now being cultivated in many parts of the world, and wherever so culti- 

 vated, frequently escapes and becomes a ruderal. 



Types of Alfalfa. — Medicago sativa is now quite generally 

 considered to be an heterogeneous species, made up of many 

 strains, varieties, and even subspecies. Westgate holds that 

 some of our hardy strains of alfalfa (Grimm, for example) 

 owe their hardiness to the possession of a small percentage 

 of the "blood" of the hardy yellow-flowered or sickle alfalfa 

 {Medicago falcata) . Numerous forms of alfalfa arise where 

 ordinary alfalfa {M. saliva) and yellow-flowered alfalfa (M. 

 falcata) grow together. These hybrid forms are, of course, 

 unstable. They have been recrossed several times with 

 ordinary alfalfa and also among themselves. Such forms 

 have been termed "variegated alfalfas." Sand lucerne 

 {Medicago media) is considered by some botanists to be a 

 natural hybrid between M. sativa and M. falcata; others 

 consider it to be a distinct species. Sand lucerne has flower? 

 ranging from bluish and purple to yellow, with numerous 

 intermediate shades. The seeds are not as heavy as those 

 of common alfalfa. The plant is a hardy type. Grimm 

 alfalfa, as has been indicated, is quite certainly a form with 

 hybrid characteristics, the parents being common alfaKa and 

 yellow-flowered alfalfa. Other well-known types of a,lfalfa 

 are: Turkestan, German, American, Arabian, and Peruvian. 



Turkestan was secured from Russian Turkestan in 1898. 

 The water requirement of the plant is low, and it also pos- 

 sesses an ability to withstand extremes of temperature. 

 The plant is ordinarily a little smaller, and the leaves are 

 narrower and more hairy, than other common sorts. German 



