Oh man, I had to learn the hard way. I harvested a hickory middle of october. Little bit of loosening to the bark. Would have been pretty easy, should have did it in Sept. Anyway, I got busy hunting so much I forgot about the 12 staves I pulled off. Holy cow. I have working with these staves since Jan, trying to remove the bark, and its like die hard blue steel. I think i am throwing sparks when I do it. Also, on a few, I got dangeriously close to going into the first growth layer.
Lesson learned. Harvest and debark in the growing season.
Now, osage I keep hearing you want to do in Winter or checking is tough to control.