Part IV.] 
PRUNING AND THINNING. 
219 
for ever divided, is for ever united. The two 
leaders are condensed in one, and the growth of 
the favoured one, in the bulk of its stem, is for 
ever doubled. But this twofold increase of the 
stem above the fork is no greater than the in¬ 
crease of the stem below the fork ; and the 
increase of that stem is in no way altered by the 
pruning : it only receives from one stem the 
same quantity of descending sap which it would 
have received from two. Nor is the whole 
quantity of timber produced by the tree altered, 
though it is infinitely increased in value, by 
uniting in one long stem what would have been 
divided into the branches. Throughout all 
forest pruning the same principle reigns, as has 
been exemplified in the case of the double- 
leadered nursery plant. Any argument to prove 
that the double increase of the single remaining 
leader deteriorates the quality of its wood, would 
also prove that the quality of the stem below 
the original fork is inferior to that of the two 
leaders, or that stems in general, which are the 
receptacles of the aggregate descending sap of 
the branches, are inferior in quality to the 
branches. 
As an example of what may by accident 
happen to multiply leaders in the growth of 
