When we first moved here we burned wood. Just for fun I attempted to dig out one of the Ponderosa pine stumps. After a day and a half of digging, sweating & swearing - I gave up. The stump was 38", was half a mile from the house and looked just fine sitting there. It took about eight years for it to rot out. There are other pine stumps that I know were cut over 100 years ago and are still pretty solid. Location, location, location - if the stumps are in an area that is naturally dry year round - my great grandchildren are still admiring them.