CHAPTER IV 



PROPAGATION BY MEANS OF ROOTS AND STEMS 



48. The primary function of roots and stems is to support 

 and maintain the plant; but these parts may also serve to 

 propagate the plant, or to produce new individuals. 



49. Propagation by Means of Rhi- 

 zomes. — One function served by subter- 

 ranean stems or rhizomes (rootstocks) is 

 to propagate the species. Each stem has a 

 bud at its end, and from this bud a shoot 

 arises. By the dying away of the older 

 part of the rhizome, this shoot becomes 

 a separate plant, although the rhizome 

 maintains its connection for years in some 

 plants. Shoots may also arise from the 

 intermediate or lateral buds, but the 

 strongest shoots usually arise from the end 

 or near the end of the rhizome. (Fig. 23.) 



50. Each successive plant is farther 

 removed from the original plant or the 

 starting-point of the colony. Thus the 

 colony or "patch" grows larger. Familiar 

 examples are the spreading patches of 

 mandrakes or may-apples, quack-grass 

 (Fig. 27), Solomon's seal, lily-of-the-valley, 

 ferns. Cannas propagate by means of 



rhizomes; so does ginger, and 

 the "roots" can be purchased 

 at the drug -store. Fig. 28 



27. Quack-grass or couch-grass. Point .,, , t , e 



out the rootstock. illustrates the spread of a 



(18) 



