34 PEACTICAL BOTANY 



for example, winter wheat is ah annual, though it does not 

 seed until the next summer after it is planted. And the cot- 

 ton plant, the lima bean, the tomato, and the castor bean are 

 instances of plants which with us are cultivated as annuals, 

 but in warm climates live several years ; the castor bean, in- 

 deed, grows there into a large, almost tree-like shrub. Very 

 commonly plants which live for more than one year have food 

 stored in their roots. 



FIG. 23. Clustered, fleshy roots of the dahlia, with much stored plant 

 food, in early spring 



st, remains of last year's stem ; sh, young shoots beginning to sprout from 

 the upper ends of the roots. One fourth natural size 



Such biennials as beets, carrots, and parsnips store up much 

 food in the root 1 during the first summer's growth, and form 

 a large tuft or rosette of leaves, but do not develop much stem 

 above ground. During the second summer the stored food is 

 consumed in the production of leafy stems, bearing flowers 

 and fruit, and in the autumn the root appears quite withered 

 and nearly dry. 



1 The underground part of the carrot and the parsnip is part stem and 

 part root. 



