PRUNING MATURE TREES 



253 



are easily injured by sun, pruning should aim to keep 

 plenty of leafage in the top to shade these susceptible 

 parts. Yet it is necessary to cut back and thin out the 

 tops of most varieties, especially of the Americana class, 

 so as to maintain a good form, a low head and enough 

 light and air to favor the production of first quality fruit. 

 The Domestica varieties, as a rule, including the prunes, 

 are pruned probably 

 less than any of the va- 

 rieties of the other 

 groups. Those varie- 

 ties, however, that tend 

 to overbear require 

 more or less thinning 

 out of the fruiting 

 wood so as to augment 

 both size and quality of 

 the fruit, to favor reg- 

 ular annual bearing 

 and to facilitate work, especially thinning and harvesting. 

 The Japanese varieties as a group will stand fairly 

 severe pruning. Special care should l)c taken to avoid 

 weak crotches (Figs. 99, 100, 102) Ijecause the Japanese 

 varieties have unusually brittle wood. In general, the 

 method of pruning employed with the apricot \a ill be 

 found to work well with the Japanese varieties because 

 the habit of fruit bearing is closely similar. \A'hen neg- 

 lected the trees tend to develop "full" and "ofT" years. 

 Annual heading back and thinning out of the smaller 

 branches will develop strong new growths of wood that 

 later serve well in fruit bearing. Pruning to thin the 

 fruit, while of some service, is not as productive of good 

 results as in the case of the peach. First quality plums 

 demand also summer thinning of the fruits. This rule 



FIG. 215— WINTER INJURY OF PEACH 

 Left one and extreme right healthy; others 



injured. Dark parts are injured wood. Light 



ones new wood forming. 



