82 PEEMANENT AND TEMPOEAEY PASTUEES. 



on for another crop, but when pastured and kept constantly down 

 the plant will provide a bite all the summer. 



The small fohage admirably fits it for lawns and pleasure 

 grounds. 



MEDICAGO LUPULINA 

 (Common Yelloiv Clover, or Trefoil). 



A fibrous-rooted biennial plant which flowers from May to 

 August, and very much resembles Yellow Suckling, but the 

 foliage is a paler green, the stems much less hard and wiry, and 

 the flowers are not so dark. The black seed-pods, which have 

 earned for it the name of ' Black Medick,' are also useful as a 

 means of identification. Trefoil starts so early in spring as to 

 give a bite before any other clover, and flowers ten or fifteen days 

 in advance of TrifoUum pratense. 



Although the procumbent habit of growth prevents it from 

 being of much value for the scythe, it affords a large quantity 

 of keep in spring, but there is no aftermath worth speaking of. 

 Primarily it is a plant for alternate husbandry, being only bien- 

 nial in duration ; still it propagates itself so sedulously by seed 

 as to be practically permanent, and as chemical analysis shows 

 the herbage to be nutritious, there is good reason for including 

 a small proportion in most permanent mixtures, especially as 

 it grows compactly and helps to make a good bottom to a pas- 

 ture. Where it is indigenous in abundance, seed need not be 

 sown, nor should it be admitted to those soils on which it is liable 

 to smother other plants. 



Trefoil endures cold better than heat, will grow freely on 

 almost any soil, and shows preference for such as are calcareous, 

 because lime is one of its necessities. Clay marl is its special 

 home. Fresh green manure does not suit Trefoil, but a top 

 dressing of a good compost or of vegetable ash generally brings 

 a full crop. All manures containing potash and phosphoric acid 

 have a magical efl^ect on its growth. 



