96 FORAGE CROPS. 



States it will endure the winters as far north as the 

 Canadian boundary. It is not likely to succeed in 

 the Canadian provinces that lie between Lake Supe- 

 rior and the Rocky mountains, but on the Pacific 

 slopes of British Columbia there should be no diffi- 

 culty in growing it when the soils are suitable. 



Place in the Rotation. As alfalfa is usually 

 sown with the intention of allowing it to remain 

 undisturbed by the plow for several years, it will be 

 readily apparent that it is not a good rotation crop. 

 In fact, it can only be used in very long rotations 

 when thus grown. But as it is sometimes sown to 

 provide hay arid pasture along with medium, mam- 

 moth, or alsike clover, it may be used in rotations of 

 limited duration, in conjunction with one or more 

 of these plants. When thus grown the rotation may 

 be the same as that adopted in growing these clo- 

 vers; that is to say, it may, with much propriety, 

 follow a cultivated crop in order to obtain a clean 

 seed bed on which to sow it. And it ought to be 

 followed by some crop that wants much nitrogen to 

 perfect it, as corn or one of the cereals. As alfalfa 

 is a somewhat delicate plant the first year, it is 

 important that it shall be sown on clean ground 

 where the weeds will not be likely to smother it. 



Soil. The soil best suited to the growth of 

 alfalfa will be measurably dependent on the moisture 

 that can be furnished to it in the form of rain, 

 through surface irrigation or from a subterranean 

 source. Loose, sandy loam soils rich in certain 

 elements of plant food, particularly lime, phosphoric 

 acid and potash, are usually regarded as the most 

 suitable for alfalfa. These soils should be deep in 

 character and should lie on sandy or gravelly sub- 



