436 FORAGE PLANTS AND THEIR CULTURE 



low trefoil has become rather notorious from the fact 

 that its seed (Fig. 50) has been much used to adulterate 

 alfalfa seed, but nevertheless the plant has some merit as 

 a forage crop. It is native to Europe and Asia, but has 



become thoroughly es- 

 tablished from Ontario 

 to the Gulf of Mexico, 

 and is also common on 

 the Pacific Coast. Its 

 wide naturalization in- 

 dicates its wide adapta- 



FIG. 50. Seeds of yellow trefoil, a, n< 

 seeds showing variation in form and size ; Of its wide Value in 

 b, natural size of seeds ; c, oval form of THvirODe 



trefoil seeds indicated ; d, a pod of trefoil. 



Stebler and 

 Schroter write : " Al- 

 though neither very productive nor persistent, still on 

 many soils where red clover is not successful this plant 

 becomes valuable because its fodder is so nutritive. It is 

 especially valuable in pastures. Because of the diffuse 

 stems and their spreading habit, yellow trefoil is usually 

 sown in mixtures with clovers and grasses, and thus forms 

 excellent pasturage. As the plant itself only lasts for 

 one or two years, it ought to be used in lays of short dura- 

 tion. In mixtures on warm and favorable soils, it reaches 

 maturity and propagates by sowing its own seeds." 



The plant is normally an annual, but with perennating 

 forms. Its small size is the principal objection to its 

 culture, but where it once becomes established, it makes 

 a valuable addition to pastures, even on very poor soils. 

 Planted thickly in late summer or early fall, the plants 

 will make a dense mass of herbage 10 to 16 inches deep 

 by the following May or June. In this way it has much 

 the same use as crimson clover, but it will withstand much 



