ONE, TWO, OR THREE YEARS DURATION 559 



Moreover, the necessary seeds should be cheap as the outlay 

 for them occurs often. 



As the ' leys ' are to be ploughed up at the expiration of two 

 or three years, the question of their durability or permanence 

 beyond this period is of no importance. 



The grasses and clovers most nearly satisfying the above 

 conditions are : — 



Red Clover. 

 Alsike. 



White Clover. 

 Black Medick. 



Italian Rye-grass. 

 Perennial Rye-grass. 

 Timothy. 

 Tall Oat-grass. 



Usually only one, tviro, or three of the above species are 

 employed in each mixture. Which individuals should be 

 selected depends upon the character of the soil, the manner in 

 which the produce is to be used, and the duration of the ' ley.' 



Red clover, black medick, and Italian rye-grass are prac- 

 tically annual and therefore only useful for one or two year leys. 

 The other plants are more durable and used when the leys are 

 left down three years. 



Black medick is chiefly employed on the somewhat inferior, 

 dry, calcareous soils j Timothy and Alsike are adapted to the 

 stiffer soils, the latter clover taking the place of red clover where 

 clover-sickness is feared. 



For grazing with sheep, white clover is usually a prominent 

 constituent of the ley. 



The following examples may be taken as illustrations of the 

 species to be employed, and the proportions of each to be used, 

 in the formation of mixtures for short leys. 



As the clovers grow freely, produce large bulk, and are more 

 nutritious than the grasses, the proportion of ground covered 

 by them should range between 50 and 100 per cent., the greater 

 amounts being taken on good soils free from 'clover-sickness.' 



