I think most siding products would burn up in a forest fire situation. Poplar bark is whats shown and its one of my favorite siding materials. Used in place of cedar shingles, its a great green alternative here on the East coast. The best part is after kiln drying there are no maintenance needs for the life of the product. No painting or sealing for life! I think 50 years is a fair claim under decent overhangs and I know of one area of poplar bark homes that have lasted 75-100 years. Its very aesthetically pleasing and many people mistake it for rock from afar. It seems to work best as accents rather than full coverage.
"If you want to save the environment, build a city worth living in." - Wendell Berry
The knights of nee want a shrubbery. And a tiny ad:
For the Love of Paw Paws Mini Manual - Kickitty-Kickstarter