The best example I have come across addressing this exact construction issue is the classic Stave Church of Norway. The principle is simple - do not let wood come into contact with soil at all. Water will leech and decay almost anything over time, so the best technique is to keep water separated from dry goods completely. What we see here is a classic Stave Church elevated on a foundation of dry stacked rock, which is the longest-lasting stone technique because mortar can also potentially deteriorate. These churches are now in the 800-year-old range because of this practice. They are maintained by coating the wood with pitch as needed, which makes most sense as this is applying like to like - the pitch came from the tree in the first place. It provides a perfect resin coating to keep the structure as dry as possible. Moisture is everywhere, it's just a matter of conducting it per the dictates of the individual climate. Working with nature as opposed to trying to beat it back, which never works long-term.
It probably rains a good amount in Norway, so fighting moisture is a losing battle, you just have to separate your materials out in a way that keeps them preserved. Stone conducts water down and away, wood supported by stone is elevated and removed from direct contact with water, therefore there is no opportunity for water to spend any real time with the wood. Ambient moisture and rain is inevitable anywhere, so the application of the resin acts as a highly effective mitigator of temporary contact with water from above. Again, conducting it down and away. the whole affair uses only natural materials, and is really the simplest way of shaping nature to suit human needs. I suspect these churches were inspired by Pagodas on someone's trade journey at some point lost to history, because of their multi-tiered roofing style and the minimalist approach to construction. In a modern sensibility I suppose you could add interior cobb or stucko walls and concrete or terazzo floors etc if you wanted extra insulation and refinement on the interior.
I once planted naturally sourced-branches from English Laurel as fence posts. I made sure to fill the bottom of the post holes with concrete before putting in the posts, then filling more concrete in around them and stacking the concrete above soil level the make a sort of incline away from the post, thus providing something of a 'sealing' and 'repelling' technique. The posts were variegated and bendy which gave a really cool effect, and I suspect they will last 50-100 years before the concrete deteriorates and the bottoms of the posts rot out, but that was fine for that project. If I wanted to make something truly legendary, I just simply would not put any wood into the ground under any circumstances. There is no technique that will stand the test of time besides keeping wood and soil separated completely. And the best material for fencing is actually just dry stacked stone. Nothing to deteriorate at all.
I've often wondered about ancient earth homes, i'm assuming which are stacked stone with soil and sod over the top. How does the moisture soaking through stay out of the interior open space? I suppose the initial stack of the stones can be done in an angles way to guide the water to flow down and away, but this would really have to be done well to work fully wouldn't it? They did it so it must have worked. I have seen open-air stacked stone huts done this way, so the rain getting in must be minimal, except for the smoke hole for the fire.
I personally think conducting water down and away is the first concern for any building project. Water is a wonderful thing, so directing it and collecting it is my primary thought when envisioning an earth home. I love soil too, but it seems that stone, in some form and application needs to provide a solid barrier from soil in order to make a dry space. Even backfilling thick concrete walls with soil is not a great idea in my opinion. I would use sand and gravel, and have a really good drain system put in. The constant moisture contained in soil is too much for anything to withstand for a truly long or even indefinite period of time.
