After a tornado came through our town, I got some nice pieces of an oak tree that came down. I left one slab ~14" thick and ~20"x30" oval as an outdoor bench that held up for year (with lots of cracks from drying". I cut some of it into ~12" cubes and sealed them for when I got some time at the lathe. Within 6 months, every one of those cubes had so many voids opened up that they were not safe to turn. I don't know how much of that was from drying stress and how much was residual stress from when the tornado took the tree down. I just know that I wished that I had gotten to those blanks before they went bad.
I look forward to seeing what you make from that oak.
If you want a challenge for some of the branches in the pic, you might try turning some 3-sided chisel handles.