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PRUNING CCLD INJURED BLUES}i:RRIES 



Cold injury to cultivated blueberries in the southeastern part of the state 

 has net been severe. The lowest temperature reported vras -19° F. several feet 

 above a field. It vras probably belo;f -20° in the field. An estimated 5 to 10 

 percent of the flower buds in this field were injured. IHrenty percent of injured 

 flower buds was the most found. The only vfood injury observed was in a planting 

 forced into late, excessive growth by very heavy nitrogen fertilization. Even 

 under these conditions the injury was not serious. 



The pruning of blueberries should be preceded by a thorough examination of 

 the field for bud aiid Tiood injury. Each fruiting bud contains several flower 

 buds. All the flower buds in a fruiting bud are seldom killed unless injury is 

 very severe. The blueberry produces more flower buds than it can mature into 

 fruit and still maintain vigor to produce succeeding crops. A loss of 20-2^ 

 percent of flower buds is no more than a good pruning and villi not be serious 

 unless followed by heavy pruning. V.liere many f lower buds have been lost, the 

 pruning ^Till need to be reduced in proportion to the loss to maintain a crop. 

 It is xvell to delay the pruning as long as possible to learn the full extent of 

 the injury. 



If there is evidence of vfood injury as revealed by broiiwiing of the tissues, 

 it is even more important to delay pruning till the full extent of the injury 

 is knovm. If the wood ijijury is light, it may be possible to give the bushes 

 a nonnal amount and type of pruning. If the injury is severe, the injured wood 

 needs to be removed and the crop reduced by thinning out or cutting back of the 

 fruiting shoots remairing. I'There injury has been severe, the object should be, 

 not the production of near normal crop, but the minimizing of subsequent effects 

 on the bush by encouraging grc-vrth rr.ther then fruiting. 



^Jhere propagating is to be done, the vrhips used snould be examined very 

 critically. If any sign of injury is fovnd, they should oe discarded. 



J. S. Bailey 



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