[Chap. XXXV 



VEGETATIVE MULTIPLICATION 



413 



sprout profusely, become increasingly abundant in subsequent forests. 

 Forests composed almost entirely of chestnut have resulted from this 

 practice. When the sprouts originate from parts of the plant below 

 (Ground, and especially from roots, they are frequently called "suckers." 

 There are many plants, such as lilac, plum, cherry, sumac, black locust, 

 silver poplar, and bindweed, that multiply vegetatively by the growth of 

 shoots, or sprouts, from adventitious buds in the roots (Fig. 189). 



4?t^ 



Fig. 189. The field bindweed (Convolvulus arvensis) multiplies rapidly by 

 the growth of aerial shoots from buds on vertical rhizomes which develop at 

 intervals from the many lateral roots. The plant pictured above had been grow- 

 ing for 14 weeks. The scale is in feet and inches. The larger shoot near the 

 center grew from the embryo in the seed. The lateral roots grow horizontally 

 for a foot or more and then curve downward. Near the bend a second crop of 

 laterals develop; when they curve downward a third crop develops from them, 

 and so on throughout the' season. Photo by J. C. Frazier, Kansas Agricultural 

 College. 



Thickets of such plants are often formed in this manner. Ordinarily 

 shoots grow from the roots of many other plants only after the tops have 

 been removed — for example, dandelion or cottonwood. New sweet 

 potato plants are obtained from old roots each season by moving them 

 From storage bins to warm moist propagating beds for a short time. 

 Dozens of new plants may be obtained from each root. Leaves of the 

 sweet potato plant may also be used as vegetative propagules. 



