S6 GENERAL PRINCIPLES. 



before dormant, they are excited into growth, and produce 

 new wood and leaves ; these send do^ai new layers of 

 woody fibre on the old stem, and it increases rapidly in 

 diameter, so that by the time it has attained its former 

 height, the base is two or three times as thick as the 

 top, and possesses sufficient strength to maintain an erect 

 position. 



Maintaining an equal growth among the hranches of a 

 tree is conducted on the same principle. Branches that 

 are more favorably placed than others, appropriate more 

 than their due proportion of the sap, and grow too vigor- 

 ously, are checked, by removing more or less of their grow- 

 ing points ; this lessens the flow of sap to that point, and 

 it naturally takes its com-se to the growing parts of the 

 weaker branches that were left entire, and thus a balance 

 is restored. 



Pruning to renew tlie Groicth of Stunted Trees. — It 

 frequently happens that trees, fi'om certain causes, become 

 stunted, and almost cease to grow ; the sap vessels be- 

 come contracted, and every part assumes a comparatively 

 dormant condition. In such cases they are cut back, the 

 number of their buds and leaves is reduced, the whole 

 force of the sap is made to act upon the small number re- 

 maining, and enal)les them to produce vigorous young 

 shoots ; these send down new woody matter to the stem, 

 new roots are also formed, and thus the whole tree is re- 

 newed and invio^orated. 



Pruning to induce Fmdtfidness. — ^This is conducted on 

 the principle that whatever is favorable to rapid, vigorous 

 growth, is unfavorable to the immediate jDroduction of 

 fruit. Hence the object in view must be to check growth 

 and impede the circulation of the sap, just the opposite of 

 pruning to renew growth. The only period at which this 

 pruning can be performed, is after vegetation has com- 

 menced. If a tree is severely pruned immediately after 



