FOB AGE CBOPS IN NORTHERN GREAT PLAIXS. 25 



HAY AND PASTURE CROPS. 



ALFALFA. 



Much of the alfalfa of the northern Great Plains is produced under 

 irrigation or has been given the advantage of favorable location along 

 creek bottoms and elsewhere. Under such conditions fairly satis- 

 factory crops may ordinarily be depended upon, even in sections 

 where the rainfall is not sufficient to insure profitable yields on the 

 uplands. (Fig. 10.) However, fields of alfalfa are not uncommon 

 even where moisture conditions are so unfavorable that the yields 

 secured are very light. The soils in most of this region are naturally 

 well suited to the growing of alfalfa. They are generally well supplied 

 with nitrogen-fixing bacteria and do not require the addition of lime, 

 as do many of the soils of the more humid sections. 



In the eastern part of the region little difficulty is experienced in 

 getting a stand; but toward the west the lack of sufficient moisture 

 frequently results in the failure of new sowings, and repeated attempts 



Fig. 10. — A field of alfalfa at Moccasin, Mont. Under average conditions in the Judith Basin 

 alfalfa maintains a good stand for several years. 



are sometimes necessary before success is attained. After the plants 

 get well established they will stand considerable drought even though 

 they do not make much growth. 



To insure success it is best to sow alfalfa in the spring, when 

 moisture conditions are more likely to be favorable. Formerly early 

 sowing was advised, but recent tests indicate that better stands are 

 obtained where sowing is delayed until from May 1 to 16. This 

 gives an opportunity to work up the land and to destroy the weeds, 

 which give considerable trouble in most of this region. Kussian 

 thistles are frequently troublesome, but cultivation destroys them to 

 a large extent. (Fig. 11.) 



VARIETIES OF ALFALFA. 



The vicissitudes of climate under which alfalfa is grown on the 

 northern Great Plains make the subject of variety a very important 

 one. Early in the history of alfalfa culture in this region, interest 

 became manifest in varieties possessing winter hardiness. It was 



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