my cherry blossom split tree trunk

Question

I have had my cherry blossom for almost 18 years and, I never water it. However, the tree trunk recently split about 10 inch near the root.

Answer 1

There can be different reasons for a trunk to split, from disease, mechanical injury and sun scald.
These links will help you.
http://plantclinic.cornell.edu/factsheets/barksplitting.pdf
https://www.gardeningknowhow.com/ornamental/trees/tgen/cracking-tree-trunks.htm