CLOVER 



A. J. PlETEKS 

 Bureau of Plant Industry, U. S. Dept. of Agriculture, Washington, D. C. 



The term " clover " is somewhat 

 loosely used and popularly includes not 

 only the true clovers, but also such 

 plants as sweet clover, bur clover, and 

 Japan clover, which, while botanically 

 quite distinct from them, have habits 

 and agricultural value very similar to 

 that of the true clovers. 



BOTANICAL CHARACTERS 



The true clovers belong to the genus Trifohum, one of the 

 genera of the pea or bean family of plants. This family is 

 characterized, among other things, by having flowers that are 

 formed of a standard, two wings, and a keel — a type well known 

 in the pea. Along with other genera, as those to which alfalfa and 

 sweet clover belong, the true clovers have three-parted leaves; 

 but they ditfer from these near relatives in having the flowers in 

 heads and the seed in small, straight pods. All members of this 

 genus are herbs ; that is, they have no woody stems. Many of the 

 species are annuals ; others, as white and alsike clovers, are peren- 

 nials ; while some, as red clover, may be biennial or perennial, de- 

 pending on the method of handling and the conditions under 

 which tjiey are grown. 



GEOGRAPHICAL DISTRIBUTIOlSr 



There are at present some 275 known species of Trifolium; 

 fourteen of these grow wild in the northeastern states, while many 

 more are found in the West and South, the extreme West being 

 especially rich in species. The clovers are essentially plants of 

 the temperate region, most of them being found in the ISTorth 

 Temperate Zone, with a few in South America and in jSTorth and 

 South iVfrica. Of the fourteen species found growing wild in the 



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