264 PRUNING. 



thereby affected; and it need scarcely be explained 

 that just in proportion as the growth of the branches 

 is retarded, so is that of the stem. It is found, on 

 dissecting any trees thus pruned, that the zones or 

 annual rings become very considerably thinner from 

 the time of the operation. So visible is this, that on 

 examining a section of a tree severely pruned, it can 

 be well ascertained what year it took place ; and one 

 observable feature is, that the zones are rarely so 

 much affected the first as the second and subsequent 

 years, showing that the injury is not experienced all 

 at once, but by degrees, modified no doubt by various 

 circumstances, such as shelter, condition of soil, age 

 of trees, &c. The object aimed at in reducing the 

 branches, Cree informs us, is to lessen the superficies 

 which the sap has otherwise to cover in the structure 

 of the branches ; hence a greater quantity is allowed to 

 go to build up the stem. 



It appears scarcely necessary to state, much less to 

 prove, that this theory is completely false, which is 

 easily known from the fact that the branches are the 

 chief laboratories or manufactories of the sap ; hence, 

 if the laboratory or manufactory is in any way injured 

 or destroyed, that which it produces must be corre- 

 spondingly influenced in an unfavourable way ; if the 

 branches which perform so important a part in form- 

 ing the sap are cut off, the current is thereby dimin- 

 ished, and the whole structure of the tree suffers. 

 Pruning, therefore, cannot increase in a direct way 

 the quantity of wood in trees, either conifers or hard- 

 woods, neither has it a beneficial effect either upon 

 • grouped plantations or those trees standing singly and 

 exposed. Branches not only assist in elaborating the 

 sap, but are the principal elaborators, whence it returns 



