HEAD FORMATION IN APPLE TREES 159 



two or three years wlien scaffold branches are being established, especially in 

 upright growing varieties. Then vigorous growth may be encouraged until 

 the trees are large enough to bear profitable crops. 



How to Prune 



The puqjose of the experiment was to find how the trees reacted to certain 

 definite treatments continued year after year. Some of the trees are now well 

 formed and seem of the type that should produce satisfactorily. Most such 

 trees are among the modified leader, central leader, and unpruned types. In 

 fact, with a little thinning out of branches, many of the unpruned trees would 

 be as satisfactory as these of any other class. Yet some of these would be 

 stronger and more satisfactory had some of their main branches been pruned 

 when small so as to prevent their outgrowing other branches. 



Both types of headed trees are unsatisfactory. They tend to be upright 

 and have too much bare space along the branches and too few laterals and 

 spurs. The globular trees not headed are intermediate. Some are strong, 

 well-formed trees; others have some of the faults of the headed trees. 



Pruning at Setting 



One-year whips may be set without pruning if not too tall. Trees over four 

 feet tall may be cut back, especially if of upright growing varieties. Leave 

 two to four feet according to the variety, taking care to have plenty of strong 

 buds on the part left. 



In pruning two-year trees, leave the strongest and most upright branch for 

 a leader, cutting it little or not at all. Remove or cut back severely any 

 branches competing strongly with this leader, as well as all strong branches 

 having narrow, weak crotches. Leave well-located, fairly vigorous branches 

 having strong crotches, as temporary or permanent scaffold branches. Cut 

 them back only for the puqiose of holding back those that are outgrowing 

 the rest of the tree. This treatment will usually remove enough top to restore 

 the balance between top and root that has been upset by transplanting the tree. 



Pruning the Second Year 



Do not cut back the leader unless it is far in advance of the side branches. 

 Remove or cut back severely any branches developing narrow, weak crotches. 

 Continue the selection of strong, well separated and well distributed branches 

 as temporary or permanent scaffold branches. Cut back any that are out- 

 growing the rest of the tree. Remove or cut back any that are nearer than 

 about six Inches, and any coming out directly above another even if separated 

 by a considerable distance. 



The Third and Succeeding Years 



It is during the second and third growing seasons that the future shape of 

 the tree is largely determined. If growth has been wisely directed during these 

 two seasons, pruning in later years consists in carrying on the development 

 already started. Remove or cut back severely branches with narrow angled 

 crotches and lacking a bridge of wood across the angle. Prune with appro- 

 priate severity any scaffold branch that outgrows its fellows. Avoid the 

 development of one scaffold branch directly above another, even if separated 

 by some distance. 



