GROWING LEGUMES IN DRY AREAS 321 



rator, but that method of threshing is more or less waste- 

 ful of seed. The yields of seed vary. As many as 15 

 to 18 bushels per acre have been obtained, but 4 to 5 

 bushels are considered a good crop. 



Good alfalfa seed is a bright golden yellow color, 

 but it may have a slightly greenish tinge. It should be 

 plump and free from shrivelled seed, and also from the 

 gray-like seeds of dodder and other noxious weeds. Be- 

 fore planting, it should always be tested as to its vitality. 



Duration of the crop. The duration of the crop in 

 semi-arid areas varies greatly with the conditions. It 

 seldom fails from lack of moisture. Should it get weedy 

 or grassy, it is usually wise to break up the crop. On the 

 bench lands it has not yet been fully determined as to 

 the time that alfalfa will continue to produce well, but 

 it will last, in most instances, for several years. Where 

 it is easily grown it may be broken up at the end of 3, 4 

 or 5 years to improve the soil for other crops. 



Breaking alfalfa sod. Alfalfa does not make a stiff 

 sod, nevertheless it is very difficult to plow, because of 

 the size of the roots. It is not easy to cut them all off 

 with the plow and thus prevent future growth. To aid 

 in this work, a share more or less notched on the cutting 

 edge is sometimes used. In some instances the land is 

 plowed shallow, and again more deeply, before the crop 

 that follows is sown. 



MISCELLANEOUS FACTS 



1. The seed of alfalfa is sometimes mixed with the 

 seed of sweet clover. The resemblance between them is 

 so .close that the presence of the clover seed can only be 

 detected by the sense of smell. There is no way of sepa- 

 rating these. 



2. When alfalfa fields have been broken up and 

 sown to grain, the plants that have escaped the plow usu- 



