WINTER INJURY 



Bearing apple trees in several orchards suffered considerable injury to the 

 trunks during the winter of 1962-1963. The bark on the injured trees was in some 

 instances split, but most frequently pulled away from the wood. Therefore, it 

 was necesfjary to thump the bark in order to determine injury. A hammer is a 

 satisfactory tool for this purpose. 



Although the winter injury was predominantly on the north side of the tree, 

 in two orchards the south side of the tree trunk was affected. 



The results of grower and personal observations revealed that the winter injury 

 was mainly confined to bearing Mcintosh trees. One grower estimated 657o or more 

 of his bearing Mcintosh trees 12 years or older were injured. Cortland, Macoun, 

 Red Delicious, Golden Delicious and Early Mcintosh had little or no injury. 



The winter of 1955-1956 was the previous time that severe winter injury 

 occurred. The Injury was most severe and extended to the lower scaffold limbs. 

 Also, it was most evident on the south side of the trees. Variety susceptibility 

 was similar to that of this past winter. 



In 1955-1956 the injury appeared to be correlated with pruning in late 

 December and early January. This was not the case this past winter. Although, 

 one grower who keeps excellent records, reported that on trees pruned January 4, 1963 

 the injury was much more severe than on those pruned January 24 to February 5. 

 The inconsistensy of plant response to environmental factors always makes inter- 

 pretation difficult. 



The main purpose of this article is to have a written account of the damage 

 and the method of treatment. Experience gained with the repair of damage that 

 occurred in 1955-1956, which was recorded in the May 1956 issue of Fruit Notes, 

 was of value this past spring. 



Prior to 1955-1956 growers used a hammer and tacks to tighten the bark to the 

 wood on winter injured trees. In 1956, gun-type staplers with 9/16 inch staples 

 were used. The staples were driven one or two inches apart in order to insure good 

 bark-wood contact. The injured area was then painted with cold water soluble 

 asphalt emulsion commonly used as a grafting compound. Mcintosh trees having very 

 little "tight bark" prior to treatment made remarkable recovery. 



In 1963, gun staplers and air guns are being used. These air guns are being 

 operated from a compresser used for pneumatic pruners. One grower is using one 

 inch crown staples of 21/32 inch length in the air gun. The same grower welded 

 a handle on a mowing machine cutter bar section (serrated) which he used for 

 scraping off the old shedding bark prior to stapling. 



---William J. Lord 

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