Pat, for basketmaking, I don't try to seperate it, just peel young trees with thin bark, cut it into strips and let it dry, then re-soak it before using (keeps it from shrinking up like it does if you weave it green.) For berry buckets, peel older trees. For making cordage or tie material, you want just the inner bark. You can ret the inner bark loose, but as many poplars as there are in the woods around here, if you look around a bit, you'll find a fallen one that's naturally retted to the right stage where the inner bark seperates easily but isn't weak and rotten.
PS-Howdy David. Haven't been on there much lately. I was wondering how y'all fared through the tornado outbreaks.