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The trees used for the pruning tests were 12-year-old. Elberta trees 

 which had been pruned uniformly previous to the experiment. Fifty trees ; 

 of uniform size, vigor, potential yield, and previous crop and growth 

 records, were selected. Ten trees were used for each of the periods of 

 pruning: dormant, full bloom, shuck fall, 3 weeks after shuck fall and 

 no pruning. The tests were conducted over a 5 year period. 



The results obtained by Dr. Havis show several advantages of pruning 

 during the dormant season. The yield of dormant-pruned trees was higher 

 than that on those pruned at full bloom, shuck fall, or 3 weeks after 

 shuck fall. Yields of dormant -pruned trees in comparison to those not 

 pruned were about the same , but the fruit was larger on the dormant-pruned 

 trees. Fruits from the unpruned trees were significantly smaller than 

 those from the trees receiving the pruning treatments. The largest fruits 

 were produced by the trees pruned latest in the season, since relatively 

 few fruits per tree remained as a result of the heavy drop of flowers and 

 fruits under this treatment. 



Fruits produced on trees pruned at full bloom or at shuck fall or 

 left unpruned, matured earlier than the ones produced on the dormant- 

 pruned trees and those pruned 3 weeks after shuck fall. 



The longest shoot growth was produced by the dormant-pruned trees. 

 But no significant difference in shoot length occurred among the trees 

 pruned at full bloom, at shuck fall, or three weeks after shuck fall, 

 although the trend was toward shorter growth as pruning was delayed. 

 Shoot growth on the unpruned trees was considerably less than with any 

 other treatment. 



The largest number of flower buds per foot of shoot length was pro- 

 duced by the dormant-pruned trees. The next largest number was produced 

 on trees pruned at full bloom. No significant difference in the number 

 of flower buds per foot of shoot-length, occurred among the trees pruned 

 at shuck fall, or three weeks after shuck fall, or those that received 

 no pruning. 



The data obtained by Havis indicate that from the standpoint of 

 shoot growth and fruit size, it is advisable to prune even as late as 

 3 weeks after shuck fall, rather than not to prune at all. 



The experiment cited above shows that in most instances growers 

 should try to prune their peach trees during the dormant season. When 

 winter injury has occurred to the buds , the degree of pruning should be 

 decided upon after examining the flower buds or after forcing some branches, 

 By following this procedure, the grower can determine the extent of win- 

 ter injury to flower buds and prune accordingly, without having to wait 

 until full bloom. If winter injury to the wood is evident, pruning should 

 be delayed until the extent of the damage is known. 



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