4 ALFALFA 



mustard yellow. The ends of the seeds are slightly 

 compressed where they are crowded together in a pod. 

 When growing, the field has a dark green color, turn- 

 ing to purple or violet as the bloom appears, and as the 

 pods ripen this is succeeded by a light to dark brown. 



BOTANICAL POSITION 



Alfalfa, or lucerne, is known botanically as Medicago 

 sativa, one of the many species of plants belonging to 

 the important order I^eguminosae. The order I^egu- 

 minosse, or legumes, includes such plants as peas, 

 beans, clovers, and vetch. They are distinguished 

 mainly by the manner in which the seed is borne, 

 usually in a pod-like receptacle which splits in halves 

 when ripe. Of late years this order of plants has 

 assumed a position of much interest and importance, in 

 so far as it has been demonstrated that, in association 

 with badlerial organisms, the plants belonging to it have 

 the power of utilizing the nitrogen of the air, which is 

 the most important element of plant-food, and the one 

 most easily depleted in the soil and most expensive to 

 replace. The atmospheric nitrogen is not available 

 to plant use except through the iaid of the badlerial 

 organism inhabiting the nodules on the roots of the 

 plants which belong to this order, called legumes. 

 The only exception to this is a very few plants of 

 other orders of no agricultural importance. 



VARIETIES 



Besides the cultivated form there are two which by 

 some are considered as varieties of alfalfa, while others 

 regard them as distindt species. They are the inter- 

 mediate lucerne (^Medicago media), and the yellow, or 



