CHAPTER XIV. 
PRUNING SHADE TREES 
P ROPER pruning is essential to success in shade tree 
development. A tree may be well planted, duly cared 
for and abundantly nourished, but the result may be most 
unsatisfactory without judicious pruning. For insuring 
development of root and branch, for producing attractive¬ 
ness of appearance, for adapting size to environment, and 
at times even for enabling the tree to live at all, pruning 
is necessary. There is sometimes a distinction made 
between pruning and trimming. When this is done, 
pruning refers to that minimum of cutting that may be 
necessary to encourage the thrifty growth of the tree and 
encourage its development along natural lines while 
trimming has reference to changing or restraining the 
form to conform to architectural features or conditions. 
The underlying principle of pruning is the establishing 
of a correct relation, as to size, between top and root 
system. In nature a definite balance of this relationship 
is maintained. In the growing of the shade tree the 
planter must assist nature in order that both upper 
growth and root system shall be adapted to the area 
available. The pruning of branches and leaf-buds 
throws all the vigor of the tree into the remaining parts 
and results in more vigorous growth for both top and 
roots. In addition to this it is necessary that the tree 
should be trimmed for the purpose of creating a symmet¬ 
rical crown, graceful outline and a height of branch which 
will not interfere, in street trees, with sidewalk traffic or 
with wires. 
The first pruning is at the time of planting. Before 
the young tree is set out, both top and roots should be 
138 
