SUNDRY AGRICULTURAL. PLANTS„ 85 



of surrounding grasses. Mineral manures alone seem to favour 

 its development. 



The botanical description and chemical analysis are given on 

 page 184, facing an illustration. 



MEDICAGO SATIVA 



[Lucerne). 



The common name of this plant is generally supposed to be 

 derived from the canton or town of Lucerne, in Switzerland. But 

 Dr. Stebler controverts this opinion, although he is. at a loss to 

 account for the appellation. Lucerne was known to. the ancient 

 Greeks and Romans as a forage plant. It is mentioned by Virgil, 

 and at the beginning of the Christian era by several agricultural 

 writers. In Persia and other Eastern countries the plant is still 

 used for horses. 



Wet summers diminish the culture of Llicerne in England, 

 but dry seasons always restore it to favour, although English 

 farmers have never appreciated its merits to the same extent as 

 their Continental brethren. In part, no doubt, this is owing to- 

 climate, and in part to soil. Lucerne is essentially a plant for 

 dry chmates and dry soils. Cold, dry air has no ill effect upon 

 it ; but moisture, with or without heat, is directly prejudicial. 

 Its duration depends more upon the subsoil than upon the 

 surface ; indeed, the nature of the surface is of small moment 

 so long as the subsoil is calcareous. In some parts of the Conti- 

 nent Lucerne remains as good a crop twenty-five years after 

 sowing as in the third year of its existence, but five years is 

 the usual term, and seven years may be considered the fair Umit 

 of its vigorous life even on suitable land. It is interesting to 

 note the diverse surface soils on which Lucerne thrives, but 

 investigation will always prove that whatever the nature of the 

 surface may be there is a substantial agreement in the subsoils 

 where this plant flourishes. The distance to which the tap- 

 roots penetrate is almost incredible. In the first season they 



