238 Principles of Plant Culture. 
420. Pruning for Symmetry aims to develop in the 
plant a head that is symmetric with reference to its trunk. 
The general principle involved is the suppression of growth 
in all parts that tend to grow beyond the lines of symmetry. 
ee ers 
Fic. 156. Pruning for symmetry. The branches growing beyond the ideal 
outline, indicated by the dotted line, should be cut off at the points indicated. 
(Fig. 156). This is best accomplished by pinching (41a) 
during the growth period, thus economizing the plant's en- 
ergy; but when the pinching has been neglected, the ~hoots 
that grow out of symmetry may be cut back during the dor- 
mant period. 
