LEGUMINOSAE— MEDICAGO 



553 



-medick (Af. lupulina) are used as forage plants on the Pacific coast but east- 

 ward are regarded as troublesome weeds, the former injurious to wool. 



Medkago sativa L. Alfalfa 



An upright, smooth perennial; leaflets obovate, oblong, toothed, obtuse 

 «maginate or mucronate; stipules entire; flowers in a short raceme violet; 

 pod spirally twisted. A valuable forage plant. 



Distribution. Common in the irrigated districts of the West, also frequent 

 eastward, but common southward; spontaneous from New England to Minne- 

 sota, Kansas, northward and westward; native to Europe and Asia. 



Poisonous properties. A large amount of the green fodder is said to pro- 

 duce tympanites, but alfalfa is, however, one of the best of forage plants. 



Fig. 303. Flowers of Red Clover. 1, a, Calyx, c, Standard. 2, f, Wings, h, keel, 4, 5, 

 Wings, 6, keel. 



11. Trifolium (Tourn.) L. Clover 



Herbs; leaves mostly 3-foIiolate, palmately or pinnately; stipules united 

 with the petioles ; leaflets usually toothed ; flowers in dense heads or spikes ; calyx 

 persistent; lobes S, nearly equal, corolla withering or persistent, claws alternate 

 to the stamen tube; stamens diadelphous or the tenth one separated for a part 

 of its length; pods small and membranous, indehiscent or dehiscent, 1-6 seeded. 



A large genus of about 250 species mostly in the northern hemisphere. 

 Many are valuable forage plants, among these are red clover (T. pratens^), 

 alsike clover (T. hybridum) and white clover (T. repefis). Several are weedy as 

 yellow hop clover (T. agrarium), low hop clover {T. procumhens), and stone 

 ■clover {T. arvense). 



The alsike clover (T. hybridum) and red clover (T. pratense) occasionally 

 produce bloat. 



Dr. Jacob Moses and A. M. Harcourt have recently described a disease 

 sometimes caused by alsike clover.^ 



I Bull. Tenn. Agr. Exp. St. 18:28 (1905). 



