Pruning for Form 101 
order, along the trunk and branches, whenever the equilib- 
rium in feeding conditions is disturbed and has to be ad- 
justed, as, for instance, when 
the tree has been heavily 
pruned, or when soil or light 
conditions have been changed. 
Although they are not neces- 
sarily a detriment, it is evident 
that they interfere with the 
development of the regular 
crown and are therefore best 
removed. It appears that 
water-sprouts are less likely Fic. 32 — An example of correct 
to form if the pruning is done pruning, we'll healed, but with 
. water-sprouts developing 
after midsummer, when a re- 
adjustment of feeding conditions without this expedient 
seems to take place. 
In setting new trees, or in the case of plant material which 
has not been trained in the nursery to form its head at a 
desirable height from the ground, this should be attended 
to first. This height depends upon the species and the 
object for which the planting is done. In specimen 
trees, and especially trees of high stature, and decidedly in 
conifers, the crown should reach down almost to the ground. 
In shade and street trees it is desirable to keep it from ten 
to fifteen feet above ground. 
In street trees and in ornamental plantings, where several 
kinds of trees stand close to each other, the pruning knife may 
be used to advantage in preventing an undue expansion 
of crown. If this is done at regular and not too long intervals, 
interference between neighboring trees and the conse- 
quent influence on each other’s form may be avoided and the 
operation be kept within the limits of a slight trimming back. 
