Pruning. 



251 



Main branches inclined to split down may sometimes 

 be prevented from doing so, by twisting two smaller 

 branches together, to form a connection between them 

 (Fig. 165). The branches thus twisted often grow to- 

 gether, forming a tie of great strength. A main branch 

 that has actually commenced to split down may often be 

 saved by passing an iron bolt through it and the re- 

 mainder of the trunk. A bolt thus inserted may become 

 entirely inclosed by later growth. 

 B STIMULATIVE PRUNING 



This depends upon the principle that the suppression of 

 growth in one direction tends to stimulate it in others. Stim- 

 ulative pruning may be employed either to stimulate 

 growth of leaves, branches and roots, or of flower-buds. 

 427. a Pruning for Growth may 

 be performed, (a) By removing a part 

 of the branches, thus reducing the 

 number of growing points and the 

 surface exposed to evaporation. 

 Plants that are not making satisfac- 

 tory growth through feeble root action, may 

 often be invigorated by this treatment, which 

 is especially useful in trees recently trans- 

 planted or weakened by overbearing. 



(b) By suppressing reproduction. When 

 growth is desired, it is often advisable to pre- 

 vent the development of flowers. Newly 

 FIG. 165. Branches of planted strawberry, raspberry and 



fruit tree tied together by * n i -u 



a graft formed of twisted blackberry plants usually make bet- 

 twigs, ter growth the first season if the 

 flower-buds are picked off. The removal of flowers in the 

 potato plant tends to stimulate the growth of tubers, 



