PRUNING ORNAMENTAL SHRUBS AND TREES 



359 



shrubs. Summer pinching or cHpping is of special use 

 during wet seasons and when the plants are over-supplied 

 with nitrogenous plant food, both of which tend to pro- 

 duce lush growths, which continue to develop late in the 

 season, but do not ripen fully before winter sets in. Such 

 wood being succulent is sure to be killed during winter. 

 It also tends to keep the trees and shrubs low-headed 

 and to develop fruit buds, as already noted. 



FIG. 294— HOW TO FORCE PEACH BUDS TO DETERMINE THEIR CONDITION 

 The twigs are placed in water in a \^■a^m room during late winter. Twigs from 

 trees that had made a large growth one summer because of having been headed 

 back severely in the spring of the pre\ious year gave only 28.3 per cent of bloom 

 when forced thus in December, while trees which made a smaller growth {not 

 headed back) gave 44.3 per cent. This shows that the resting period ends earlier 

 on trees making smaller growth. 



268. When ornamentals form blossom buds. — ^Shrubs 

 and trees which bloom in the spring develop their flowers 

 from resting buds formed during the previous summer. 

 As in the case of fruit trees the buds are protected by va- 

 rious devices, such as thickened, woolly and waxy bud 

 scales. The fact that the flowers are in rudimentary 

 form and are ready to open under favorable conditions 

 may be proved by placing twigs of "pussy" willow, peach 

 (Fig. 294), forsythia (Fig. 295) and other very early 



