New Plants without Seed 



121 



distance from the parent, and in a few years they will travel 

 far up or down the mountain. 



A great many of the Cape plants reproduce by bulbs. 

 They may lie dormant in the ground for years. After the vege- 

 tation has been burned off these bulbs have a chance, and 

 then send up flowering stalks which turn the blackened veld 

 into a garden. 



New plants are obtained by cuttings from old ones. Some- 

 times the stock is cut back so as to obtain a supply of shoots 

 for this purpose. It is in this way that sweet potatoes are pro- 

 pagated. Kleinia articulata^ Haw., Fig. 108, which grows about 

 Uitenhage, propagates naturally by cuttings. The fleshy stems 

 are jointed or constricted at intervals. A 

 strong wind breaks the plant at these joints, 

 and new shoots start from the axils of the leaves 

 In a seed the first root is formed ready to 

 push down into the soil. In reproduction 

 without seed (vegetative reproduction), new 

 K roots have to be formed from the stem ; these 



roots are called adventitious roots. 



Vegetative reproduction occurs when 

 plants grow in the shade or in rich soil. 

 When the soil becomes exhausted, seed will 

 be formed. 



FIG. 109. Grafting ; d, the stock to which the graft is attached. The 

 various elements in the process of budding. (From Thom6 and Bennett's 

 "Structural and Physiological Botany".) 



Vegetative reproduction is sure and economical, a disad- 

 vantage arises from the close crowding of new plants. 



