PRUXING PRINCIPLES 119 



Daldwin apple, notorious for its "off years," what may not 

 be accomplished with other varieties ? 



So far as the author knows, Mr. Wells practices only 

 summer thinning; but winter thinning produces similar re- 

 sults, for it conserves energy. This conservation can be most 

 easily noted in apples and pears because of the spur method 

 of fruit bearing. In these fruits there is normally an alterna- 

 tion of cluster bud and branch (spur) bud development. 

 This is due to the demand made upon the spur for food to 

 develop the fruit, a demand that usually prevents the forma- 

 tion of a blossom bud on the spur during the same year as 

 a fruit is developed on that spur. While the fruit is being 

 developed the spur has only enough surplus energy to de- 

 velop a branch (spur) bud near the union of the fruit stem 

 with the spur. To induce annual fruiting, the trees must 

 either be extra well fed or the fruit must be thinned. The 

 former is generally not as certain as the latter. 



One way in which annual bearing may be induced is to 

 remove all the fruits while young from some of the spurs 

 and only the inferior ones from others. Thus fruit buds 

 should develop on the empty spurs and none on the bearing 

 ones, and an alternation of fruit bearing would tend to be 

 developed on each set of spurs ; but one set would bear in 

 the even years and the other in the odd years. Thus the tree 

 should never overbear in any one year, and the grower 

 should always have at least a partial crop. This method, if 

 applied while the trees are young, requires less work than 

 may at first appear, because after once getting a start it will 

 at least partly take care of itself. Whether mature trees 

 with set alternate year bearing habits can be made to bear 

 annually is .a question yet to be decided. Much of the suc- 

 cess of the plan will depend upon the character of care given 

 the orchard. 



What has been said under this heading as applying to 

 thinning of the fruit applies with equal force to the thinning 

 of the fruit-bearing areas of the trees. 



