260 



VEGETATIVE PROPAGATION 



Layering is a modification of cutting. It consists in 

 bending down a stem and covering it with earth. Deep- 

 notching or ringing the bark of the part buried usually 

 hastens the rooting of the stem. 



part of the organism 

 may be grafted on to the 

 diseased bone. But, to 

 a large extent, grafting 

 of tissues, bones, and 

 even organs is still in 

 an experimental stage 

 and has not proven suc- 

 cessful in all instances. 

 Natural methods of 

 vegetative propagation. 

 Layering , another 

 method of propagation, 

 often occurs without 

 the assistance of man. 

 In many cases the 

 branches of a tree or 



brush mav bend down until thev come in contact with the soil. 



Sometimes thev become covered with soil. If there is sufficient 



w^armth and moisture in the soil, the branches will develop roots. 



Frequently, after developing roots, they break off from the tree 



and form an entirely new plant. The raspberry, with its arching 



stems, illustrates this type 



of propagation. 



Runners are branches 



that trail along the ground. 



Sometimes, the ends or 



joints of these branches 



come in direct contact wdth 



moist soil. Roots and, 



finally, a shoot develop at 



this point, forming a new 



plant. Strawberries, as 



t^unnen 



parent. 

 plccrLt> 



yoxznS 



-plcCT>^ 



When runners are found in plants, they may be used 

 as an easy and rapid method of propagation. 



