132 ELEMENTARY AGRICULTURAL OIIEMRSTRY 



Lupines are somewhat too shrubby and woody to yield good 

 fodder, though sometimes used for sheep. Three species are 

 chiefly used — the white {Lupinus albus), the blue (^Luj^inus 

 hirsutus or angustif alius) , and the yellow {Lupinus luteus)^ 

 Lupines contain a bitter alkaloidal constituent, and are not 

 readily eaten by cattle or sheep ; moreover, they are sometimes 

 poisonous. The poisonous property can be destroyed by 

 steaming under pressure. They grow well on light, salldy soils, 

 and are often used as green manures. 



Average Composition of Leguminous Seeds. 



Though leguminous seeds (and also the leaves, stems, and 

 roots) are so rich in nitrogen, they usually can grow well in 

 soils comparatively poor in nitrogenous matter, provided 

 mineral plant food be abundant. This is due to the power which 

 they have of obtaining nitrogen from the air by the aid of 

 micro-organisms in tubercles on their roots (see chap. vi. 

 p. 105). 



3. Miscellaneous Seeds. — Buckivheat (Polygonum fago- 

 pyrum) is grown in certain parts of Europe, being largely used 

 as poultry food, and also for pig- and cow-feeding. Its flowers 

 furnish excellent pasturage for bees. "When sown with a 

 cereal — e.g., oats or barley — it furnishes an excellent green 

 fodder. 



