Most of their fiber comes from hardwood logs. If they don't get the bark off before chipping the result is a dirty pellet. Hardwood logs are harder to get the bark off from what I have been told. I tried emailing Jeff Nichols, But no reply and the email came back as failer. I don't think he works for them anymore. I was going to ask what was up? I see more ash this year than last. The heat also dropped a we bit. So I didn't purchase anymore. I started looking for others and the PTL's(more heat and also a bit cleaner). Timber Heats(more heat and definitely cleaner) were what I went after. Good news is I didn't get the long pellets in what I tried. Dollar for dollar they didn't make the cut. Nothing like the initial testing I did which impressed me. A bit sad really! Hopefully they have eye's here so they can see the chatter. Most of the people I talked to that bought them, Probably will have second thoughts due to the ash content.