We use aspen. We had one bag that was coarser, with some chunky/splintery pieces. What we are using now has a wonderful texture. It's much softer and finer. I think there can be a lot of variety in the texture and fume levels of shavings from the same species of trees. Also a difference in the dust levels. Some of this has to do with the brand. I don't know how often there are big differences from bag to bag in the same brand. I'm sure some brands have better quality control than others.