12 TREE WOUNDS AND DISEASES 



tar or other protective composition, and filling 

 with cement will usually put matters right in 

 preventing the spread of decay and aiding in 

 the callusing over and healing of the wound. 



But, however desirable it may be to repair 

 hollow trunks, yet a great amount of discrimi- 

 nation is necessary in deciding which trees 



Bad effects of pruning. 



should be operated upon, especially in the case 

 of such as are reduced to mere shells and are 

 not likely to derive benefit commensurate with 

 the labour and the cost of materials involved 

 in bracing or filling. 



Young, healthy, vigorous growing trees, that 

 have become damaged or diseased, should in 

 the majority of instances be attended to ; but in 

 the case of old specimens on which a great 

 amount of labour and money would require to 



