Hackberry stave, should l back it?

[Don Armstrong]

I traded for a couple hackberry staves a few years ago. I started on one about 4 years ago. I was told l should torch the belly. Can't remember who or why. Old age is not the golden years lt broke when l was tillering. It was a complete failure. Broke straight across the back. Looked like it was cut. The other stave is 60" end to end. What do l need to do to not repeate my failure. Would like to get 45@27 if possible. Thanks for any help, Don