RED CLOVER 



365 



ature, humidity seems to be more injurious. Under such 

 conditions, the Orel variety quickly shows signs of distress. 

 427. Effect of shade. Red clover is often planted in 

 orchards as a cover crop. It does not thrive very well in 

 shaded places and mostly disappears after the first season. 

 Stebler and Volkart report an experiment in which a mix- 

 ture containing red clover was grown on two plots, one 

 of them artificially shaded. These plots were observed 

 six years and the percentage of clover plants determined 

 each season, with the following results : 



428. Life period. Red clover is commonly said to be 

 a short-lived perennial. As a crop it is nearly always 

 treated as a biennial over the principal area of its distri- 

 bution in America. In the Southern States, it is often 

 grown as a winter annual, as it does not as a rule survive 

 the hot summers and such weeds as crab-grass. In the 

 Pacific Northwest and northern Europe, red clover fields 

 often yield satisfactorily for three years. 



Individual plants of red clover may live six to nine 

 years, but comparatively few live over three years. To 

 some extent, the length of life period is a varietal character, 

 both short- and long-lived strains being secured by selec- 

 tion. Pastured plants persist a long time and probably 

 much longer than when not grazed. On the other hand, 

 but few plants survive after a seed crop has been harvested 

 from them. 



