SOME GENERAL PRINCIPLES J 



in any part of the United States or Canada in which 

 moisture is sufficiently present. Japan and burr 

 clover grow best south of parallel 37° and east of 

 longitude 98°. Sweet clover will grow in all the 

 States and provinces of the United States and Can- 

 ada, but has highest adaptation for the Central and 

 Southern States. 



With reference to adaptation to soils, medium 

 and mammoth clover grow best on upland clay loam 

 soils, such as have sustained a growth of hardwood 

 timber, and on the volcanic ash soils of the Western 

 mountain valley. Alfalfa flourishes best on those 

 mountain valley soils when irrigated, or when these 

 are so underlaid with water as to furnish the plants 

 with moisture. Alsike clover has much the same 

 adaptation to soils as the medium and mammoth 

 varieties, but will grow better than these on low- 

 lying soils well stored with humus. Crimson clover 

 has highest adaptation for sandy loam soils into 

 which the roots can penetrate easily. Small, white 

 clover has adaptation for soils very similar to that 

 of alsike clover. Japan clover and burr clover will 

 grow on almost any kind of soil, but on good soils 

 the growth will, of course, be much more vigorous 

 than on poor soils. Sweet clover seems to grow 

 about equally well on sandy loams and clay loams, 

 but it has also much power to grow in stiff clays and 

 even in infertile sands. 



Place in the Rotation. — All the varieties of 

 clover discussed in this volume may be grown in 

 certain rotations. Their adaptation for this use, 

 however, differs much. This increases as the natu- 



