Pruning. 241 
trunks insufficiently developed to support the head, when 
planted by themselves. To remedy this defect, we promote 
the formation of new vascular bundles (68, 124) by inducing 
branching, which we accomplish by cutting back the top in 
proportion to the slenderness of the trunk (422). 
b—of the Branches. Trees expected to support heavy 
crops of fruit, or to endure high winds, should have branches 
developed with 
special reference 
to strength. In 
such cases, sev- 
eral medium to 
small branches 
are better able to 
endure the strain 
than a few large 
ones (245), and 
the loss to the 
tree of a small 
branch, should it 
occur, is less seri- 
Fic. 160. Showing how density of growth is promoted 
{right hand side) by persistent pinching of the terminal 
growing points. ous than that of 
a large one. Forming the head of fruit trees of three or 
four main branches is to be discouraged for this reason. 
Several small branches from a common trunk are better, 
and these should be encouraged to leave the trunk at nearly 
right angles (Fig. 155). Forks in the trunk of fruit trees, 
dividing the wood into two nearly equal parts are objection- 
able, as one or the other part is very liable to split down 
under the weight of a heavy fruit crop. 
426. Main Branches Inclined to Split Down may 
sometimes be prevented from doing so, by twisting two 
