Some people say it's best to use only heartwood, some say the sapwood is fine on the back. I had two large trees that had to go this spring. Kept the bark on as it wasn't loose yet, but stripped it off a couple of billets as an experiment. Sealed the ends with boat lacquer. Got like 17 full length staves, and a lot of short staves and billets, most of it with quite a lot of character.
So far, none of it is checking in my rather moist Danish climate (although we did just have a very dry April), not even the billets where I removed the bark. Haven't seen any bugs, but maybe they're in there
I'm keeping it stacked loosely on a table in an open carport.
Right know I actually have three pieces in the oven, making them ready for measuring density of the wood, and I have some shorter pieces in my drying room. I'll be doing some breaking tests of comparable pieces with/without sapwood, to judge for myself how it stands.
Was considering doing a Tim Baker standard bend test, but I think it will be difficult for me to get those pieces precise enough, so now I just think I'll get them close, and then bend them over my knee.
Anyway, sorry for hijacking your thread, I'll probably be making a post about it when I've done it.