Odd question to me as North America has so many options for durable softwood timbers- certainly from my perpective
"Sort of"
Nothing with quite the workability, stability, and durability of mahogany. (Yeah, it grows in Florida, but not in commercial quantities, and not at "favorable" pricing. WRC & Redwood are too soft and redwood does not have much strength, and is about the only wood that shrinks and expands noticeably in length as well as width.
Timbers that used to be considered durable and would be suitable, like cypress, are no longer reliable. I had good luck with cypress "many" years ago, but a couple jobs in the past 15 or so years went punky and rotted out faster than North eastern white pine probably would have. Which is also no longer the durable wood it was in the 19thC. You can get old growth cypress and sinkers, but the price is astronomical. I used to use Douglass fir for out door trim that was to be painted, but it is difficult to source on the east coast, especially with the sapwood cut out, and vertical grade that holds paint is expensive beyond the application. Port Orford Cedar is a niche wood now. etc.
Alsakan Yellow Cedar looks intriquing. But it is not much sold in the lower 48. I imagine it may be more common on the export markets than domestically. I really only learned of it from Chris via this post. It appears it would cost about twice what Khaya does; and does not provide quite the look desired for this installation. Would love to use it if as good as what I've recently read.
In hardwoods, American cherry heartwood is durable, and I really like black walnut which is extremetly durable. The problem with these timbers gets back to cost. In a "run of the mill" load of either, in 8/4, it is difficult or expensive to acquire it with no sapwood (which rots fast). Both can be had in sizes and grain run suitable for doors, but the price gets well above competing imported timbers.
One of the biggest producers of black locust is very hear me. I have gotten quite a few feet of free samples over the years & dry some in my loft for sills and such. But they do not dry it (kiln) and the good stuff except what you find laying about, tends to go to distribution yards or is pre-bought. Black locust is tough to source in grades suitable for doors and large architectural work "quickly" and really needs to be inspected. It is milled and shipped as it grows with bark inclusions and lots fo knots and growth defects. I have sound, thick pieces, rather like the wood, but it is just not "convenient" for something like a door project. That said, I need to lay in some and dry it. Till it is sourced, selected, and dried, it ends up in the same ballpark price as imports like Spanish Cedar and Khaya. It is dense, so when it decides to warp, it is rather adamant.
Khaya/African mahogany was the best price locally, I have used the wood in the past including outdoor applications, so yesterday committed to 1,000 ft of 10/4. Should be here next Wednesday. About enough time to clean & organize the shop of all the metal stuff & chips strewn about from the last 6 months work. I will be glad to get back to wood chips, bigger pieces, and more exercise!
smt