Part IV.] 
PRUNING AND THINNING. 
217 
plantation has been spoilt by letting the wind 
in.” 
Thinning and pruning should work together, 
and both should be gradual and annual. By 
rearing timber moderately close from the begin¬ 
ning, increasing the distance of the trees directly 
as their size, and thus depriving the sides and 
the lower parts of the stems of light, we not 
only encourage the heads to grow upward, but 
prevent the over-growth of side-boughs. All 
side-boughs which are to be taken away, should 
be gradually sawed off before they die and 
while they are small, since the new annual 
growth over a wound is curved till it is wholly 
healed. 
All branches, though they may be said to rob 
that part of the stem which is above them, feed 
that part which is below them with their de¬ 
scending sap. The growth of branches which 
are gradually taken off from the side of a tree is 
transferred to its head; and the descending sap 
from this additional new growth of the head, 
increases the bulk in girthing of the whole long 
stem, instead of being wasted on the increase 
of side-branches. If, indeed, too many side- 
branches are taken off at once, so that the 
diminished head cannot by extra growth elabo- 
Pruning does 
not increase the 
aggregate quan¬ 
tity of wood 
made by a tree; 
but, by improv¬ 
ing its location, 
increases the 
measurable 
timber. 
