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We have one grower in Massachusetts who has summer pruned 

 with a tractor-mounted sickle bar for the last 3 or 4 years. 

 He believes red color is increased on the hedged trees and that 

 the practice reduces the cost for winter pruning. 



Resulte. We compared the effects on growth and fruit quality from 

 winter pruning and summer pruning. The fruit quality measurements 

 include fruit size, soluble solids (sugar content), fruit flesh 

 firmness, fruit flesh calcium content, and senescent breakdown 

 during storage. 



The corrective winter pruning or corrective winter pruning-plus- 

 summer pruning procedures reduced the problem of tree crowding in 

 the block of Red Prince Delicious trees. However, corrective 

 winter pruning-plus - summer pruning in comparison to corrective 

 winter pruning had little or no effect on growth or fruit quality. 



Summer pruning has been suggested as a technique for devital- 

 izing trees in crowded plantings. The overall growth of the Cort- 

 land trees, as indicated by trunk circumference increase, was 

 reduced by summer pruning. Nevertheless, terminal growth the year 

 following summer pruning was greater than on the dormant-pruned 

 trees. The Red Prince Delicious trees also were not devitalized 

 by summer pruning. The only consistent beneficial effect of summer 

 pruning was improved red color of Mcintosh apples from trees 

 receiving the dormant-type mechanical hedging, or the cutting to 

 the first fruiting spur summer pruning treatments. 



Advantages of Summer Pruning 



1. Increase red color development on some varieites. 



2. Could provide work for employees experienced in pruning during 

 the slow season, in some orchards, prior to harvest. 



3. Reduce the amount of pruning necessary during the winter months. 



Disadvantages of Summer Pruning . 



1. Finding the time to prune. 



2. It may not reduce terminal growth the year after pruning which 

 is the primary cause of tree crowding. 



3. In most cases, there may be either no effect of summer pruning 



or the responses may not be consistent from year to year, or they 

 may be undesirable. Smaller fruits, lower soluble solids (sug.T 

 content) , more storage scald, bitter pit and cork spot are 

 examples of undesirable responses in our experiments. 



