Certified GKH Gardening Expert
The weather could be the reason that the bark split. Cherry trees have thin bark and if temperatures have fluctuated significantly in a short period (such as 70 F to 90 F), the bark could have split due to this. It should heal on its own, especially if the wound is not weeping or splitting further. If the split is widening, you can try protective paper (sold at nurseries) to help hold it together while it heals. Do not cover the wound with tar or any other permanent substance as this can trap disease in the wound.