Bois d'arc (Bodark) is the most rot resistant wood I know of. There are houses setting on Bodark blocks that have been against the soil for over 100 years and fence posts that are older than that. I have never used it for lumber and it might warp badly if used green. Once dried it is tough as nails and easier to work with metal working tools than wood working ones. I have done this for pistol grips.


Evan