Answer: It could be related to weather extremes. Sunscald usually occurs on the southern side of a tree's trunk, and can happen in summer and winter. The sun actually dries out and burns the bark, which splits. On sunny winter days, the quick plunge from warm sun into a cold night can cause the bark to split open.
However, the University of Nevada Cooperative Extension office in Reno has Master Gardeners who will know if there is another problem affecting fruit trees in your region and recommend treatment. Good luck!
P.O. Box 11130
5305 Mill Street
Reno, NV 89520-0027
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