446 FUNDAMENTALS OF FRUIT PRODUCTION 



At first glance these records of yields from summer and winter pruned 

 trees seem contradictory. As is the case with the corresponding records 

 of shoot growth, however, they can be reconciled. It has been pointed 

 out that fruit production depends on (1) the formation of fruit-producing 

 wood and (2) on the proper functioning of that wood. Furthermore, 

 different kinds of fruits have quite unlike fruiting habits and the processes 

 culminating in fruit production may be quite different in one from those 

 in another. The effect of summer pruning on fruitfulness, therefore, 

 is not a simple question, but rather a series of questions each of which 

 must be answered in turn. 



Among the major aspects of the summer pruning problem may be 

 stated the following: (1) The concentrating effects of different kinds and 

 amounts of pruning at various times during the growing season, (2) 

 The relation of diverse summer pruning treatments to shoot growth 

 both of the current and of the following season. (3) The influence on new 

 spur formation. (4) The effect on fruit bud formation — on spurs and 

 on shoots. (5) The relation to the intake of nutrients and to the manu- 

 facture, translocation, storage and utilization of elaborated foods. (6) 

 The influence on color and size of fruit. These questions are not entirely 

 distinct; they are inter-related and inter-dependent. Since few data are 

 available concerning some of them, any discussion at this time must of 

 necessity be incomplete. It is attempted here on a few aspects only of 

 the general problem, those which have more or less immediate practical 

 bearing and on which the evidence seems reliable. 



Summer Pruning to Develop Framework. — Data have been presented 

 concerning the influences of summer pruning on vegetative growth in 

 general and on new shoot formation in particular. No further attention 

 is devoted here to this problem except to indicate a rather special use 

 of early summer pruning in developing the framework of young, strong, 

 vigorously growing trees. 



Trees of many kinds growing under favorable conditions often develop 

 shoots 23^^ or 3 feet — and sometimes more — in length during their second, 

 third and fourth seasons in the orchard. Occasionally they make such 

 growth their first season and shoots of this character are not at all 

 uncommon as the trees grow older. Ordinarily most of this shoot growth 

 is cut away in the annual dormant season pruning, some being taken out 

 entirely and the terminal half or even three-fourths of each remaining 

 shoot generally being removed. This heavy cutting back is necessary 

 for securing a strong framework and a compact type of growth. The 

 question naturally arises whether these trees can be pruned in mid- 

 summer shortly after the shoots have attained a length equaling that to 

 which they would be cut back at the usual winter pruning. This would 

 then be followed by the production of secondary lateral shoots, many of 

 which could be saved with little or no heading back at the following 



