EXPERIMENT STATION BULLETINS. 389 



and to outward growing side branches. The dead and weak wood should 

 then be removed. The smallest twigs in the middlejofithe tree can some- 

 times be knocked off with the pruning tools without serious injury and with 

 much saving of time. The trees should then be thinned out, leaving only the 

 most vigorous, well distributed wood. A good growth, well lined with fruit 

 buds, will usually result the following season. During the following winter 

 this new growth should be thinned out and headed back, leaving a good sup- 

 ply of fruit buds. 



Renewal of Fruiting Wood — In many old peach trees the fruiting wood is 

 scarce and far removed from the ground, and the trees seem to lack vigor. 

 If the fruit buds in such trees have been injured to such an extent that little 

 or no fruit will be produced during the coming season, these trees may be 

 lowered, renewed, and thus shaped to produce better crops in future years. 

 The amount of cutting back will depend entirely on the shape and condition 

 of the individual tree. "Dehorning," as generally defined, is advisable only 

 under special conditions. If the trees have become quite upright, it will 

 usually be advisable to head the main branches back to lateral, almost hori- 

 zontal, branches; probably removing some three to five years' growth. If 

 they have not attained a great height, but are lacking in vigor and the fruiting 

 wood is scarce, some two to four years' growth of the main branches should 

 probably be removed. This, in conjunction with proper fertilization and 

 cultivation, should result in the formation of a large amount of vigorous 

 growth which may be thinned out and headed back the following winter. If 

 the heading back is very heavy, such as might be termed "dehorning," there 

 is danger of a long, thick growth being produced and the lower parts being so 

 shaded as to prevent the formation of many fruit buds where they are most 

 desired. Again, such drastic treatment usually results in two years without 

 fruit. 



Pruning Winter-Injured Fruit Trees — During occasional severe winters 

 the peach wood becomes injured, as indicated by the brownish color of the 

 sapwood. Although "dehorning" or severely cutting back such injured 

 bearing trees has been quite generally practiced, investigations and observa- 

 tions following the injury during the winter of 1917-18 are conclusive enough 

 to warrant the grower employing less severe practices. Trees in which the 

 longer branches were cut back into three- and four-year-old wood and less 

 prominent branches more lightly headed seemed to give the best response. 

 In fact, it would appear that no pruning would give better results than 

 "dehorning." Again, better results will evidently be obtained if the heading 

 back is delayed until after the sap has been active for a few weeks. 



As previously mentioned, if the fruiting wood becomes scarce and far re- 

 moved from the trunk, peach trees should be lowered. Advantage should be 

 taken of a season when it appears that a light crop will be produced to do 

 this work. For this reason it is sometimes recommended that pruning be 

 delayed until the prospects for a crop can be determined or until after blos- 

 soming. Experience has shown that if pruning is thus delayed, some of the 

 trees will not be pruned. It therefore seems best to preceed with the regular 

 pruning in the winter or early spring; then, if frost ruins the prospects of a 

 crop, it is not, much trouble to go over the trees a second time andcut them 

 back into wood three or four years old. 



