262 REPRODUCTION 



Layering is usually more successful than propagation by 

 cuttings, for the latter are liable to die before a root^system is 

 developed adequate to their requirements : in the process of 

 layering the shoot remains attached to the parent until it is 

 rooted, during which time it derives its water-supply and a 

 certain amount of food from the latter. 



Currants and grapes are readily increased by layers, and the 

 process is adopted for the rapid production of apple, pear, plum, 

 quince and other stocks which are subsequently employed for 

 budding and grafting purposes. The layering of these usually 

 takes place in autumn, the layers being left attached to the 

 parent about twelve months or until a satisfactory root-system 

 is developed, after which time they may be completely severed 

 from the parent and planted out. 



6. Budding and Grafting. — In the process of budding, a bud is 

 taken from one plant and inserted into the stem, or stock as it is 

 termed, of another; mgrafiinji a portion of a shoot with several buds 

 upon it is treated in a similar manner. The shoot, which in the 

 grafting process is inserted into the stock, is termed a. graft or scion. 



The inserted bud and stock or the scion and stock when 

 properly treated become organically united with each other and 

 behave as one plant. The roots of the stock supply the bud or 

 scion attached to it, with water and other ingredients from the 

 soil, and the leaves of the shoots developed from the bud or 

 scion elaborate plastic material for the nutrition and growth of 

 the root. Nevertheless, in nearly all cases the scion and stock 

 preserve their own individual morphological peculiarities, and 

 in this respect behave as distinct, separate plants. 



It is stated that in some instances budded or grafted plants 

 give rise to shoots which in form of leaf, colour of their flowers, 

 and other morphological characters, resemble those of the scion 

 and those of the stock as well. Shoots produced in this manner 

 with such blended characters are described as graft-hybrids- 

 they are of very rare occurrence. 



