Bob Couch replies: Mahogany, white oak and teak are both all used extensively in boat building and can receive a nice finish, however, any natural finish requires annual or at the very least semi-annual maintenance. Cyprus is a wood that grows in standing water and is very rot resistance however it has a light somewhat non-descript color and not that suitable for a natural finish but will hold a painted finish very well.
Steve Costain replies: Mahogany, Cedar, Ipe.
Garrett Hack replies: In terms of local woods, if you can find some clear white cedar, that lasts very well, as does black locust although it’s really tough and not so easy to work, and white pine heartwood. Other choices are western red cedar, ipe, garapa, larch and of course teak.