I heat solely with wood. Sell firewood. Ran into a deal I can't pass up on mill ends. 20-24 in lengths 10x10 through 14x14. Untreated. I'm currently sitting on approximately 25-27 cords. Thinking about getting 70 per week until the end of September. Cracking them once and stacking them and forgetting about them for 4-5 years. Good for the overnight burns. Anyone else here burn em. I've heard rumors that even untreated mill ends are hard on the chimney. Any truth to this? And why would this be? I'm so many years ahead with my personal use supply I can let them season 4-5 years. They need it as its mostly oak with a little maple mixed in. I just can't pass up the deal.