J)- 



Studies with Cortland 



This study was initiated on 6-year-old on Mailing 7 root- 

 stock planted at 14 foot x 21 foot spacing. These vigorously 

 growing trees were not croAvding when the treatments were started, 

 but if some growth restriction was not used a crowding situation 

 would have soon developed. The summer pruning treatments in this 

 experiment were as follows: 1) control (dormant pruning), 2} dor- 

 mant pruning-plus- summer pruning in early July, and 3) dormant 

 pruning-plus- summer pruning in early-August. 



The summer pruning procedures consisted of cutting shoots back 

 to the first fruit (the terminal apple on 1 -year-old- wood) and/or 

 a lateral branch originating from 1- or 2-year-old wood. Some 

 upright growing shoots also were removed. 



Dormant pruning-plus - summer pruning in early August in com- 

 parison to dormant pruning restricted trunk circumference increase 

 consistently and terminal growth the year after pruning was greater 

 (Table 2). Otherwise, there were either no effects of summer 

 pruning, the responses were not consistent from year to year, or 

 they were undesirable. Examples of undesirable responses are 

 smaller fruit, lower soluble solids (sugar content), more scald, 

 bitter pit and cork spot (Table 2) . 



Table 2. Effects of sumnier pruning on growth 

 of Cortland apples. 



fruiting and quality 



Parameter 



1978 



Responses 



1979 



1980 



Growth 



Trunk circ. incr. 

 Terminal growth 



Decrease (J&A)' 



Decrease (A) 

 Increase (A) 



Decrease (J&A) 

 Increase (J&A) 



Fruiting 



Flower bud formation 

 Fruit set 



No effect 

 No effect 



No effect 

 No effect 



Fruit qu al ity at harvest -' 

 Fruit size 

 Flesh firmness 

 Soluble solids 

 Red color 

 Bitter pit 

 Flesh calcium 



Decrease (J&A) 

 No effect 

 Decrease (J&A) 

 Increase (A) 

 No effect 

 No effect 



No effect 

 No effect 

 Decrease (J&Aj 

 No effect 

 No effect 

 No effect 



No effect 

 No effect 

 Decrease (J&A) 

 No effect 

 No effect 

 No effect 



Fruit q uality after storage 

 Flesh firmness 

 Breakdown 

 Scald 

 Bitter pit & cork spot 



Decrease (J&A) 

 No effect (J&A) 

 No effect 

 No effect 



No effect 

 No effect 

 Increase (J&A) 

 Increase (J&A) 



No effect 

 No effect 

 No effect 

 No effect 



July and August pruning treatments. 



To determine the effects of summer pruning on fruit quality, the fruits were 

 sampled near the pruning cuts. 



