So I went with my new ms310 with the 20" bar and tried the biggest trunk I could find. I didn't measure it, but here's a picture of the rounds that are 18" long. I'm assuming this is white oak because it's not rotted very much at all like Red Oak does. I love cutting seasoned wood though. SOOOOOO much better than green! Next is a picture of the load after splitting.... still have 1 more round to go (4 total). Then my next project....