CHAPTER XVII 



OTHER CLOVERS. ALSIKE, HUNGARIAN, 

 WHITE AND SWEET 



THE genus Trifolium comprises a large list of species 

 both annual and perennial, all of them confined to regions 

 of temperate climate or at least temperate during the grow- 

 ing period. Red clover is by far the most important eco- 

 nomic species, but where there is difficulty in growing this 

 crop other species, especially alsike and white clover, are 

 very valuable substitutes. The clover-like plants of the 

 genus Melilotus are also useful and worthy of more atten- 

 tion than they have heretofore received. 



ALSIKE CLOVER (Trifolium hybridum) 



476. Botany of alsike. - The alsike clover is so named 

 from a place in Sweden where it is much grown. It is 

 also called Swedish clover. The scientific name was so 

 given because Linnaeus erroneously believed it to be a 

 hybrid between red clover and white clover. 



Alsike is native to the temperate portions of Europe 

 and Asia and also occurs in Algiers. It is rare, however, 

 in southern Europe. The plant is very variable, but 

 only a few forms have received botanical names. Ascher- 

 son and Graebner consider that cultivated alsike is a sub- 

 species (Trifolium fistulosum Gilibert), differing through 

 long cultivation in having larger, less toothed leaves, 

 larger heads and longer calyx teeth. Another subspecies 



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