Comment by bluGill

When I was a kid Dutch Elm disease was killing all the elm trees around me so that is what everyone was heating with. An elm log that is just large enough you need to split it can stall out a wood splitter (not every time, but you will get several in a day of splitting). When splitting by hand it is common to have the handle of the maul sticking out of the log and you can't see it from the top where it went in, you just keep beating it hoping it eventually goes.

Then we got a large oak tree once, logs you couldn't even life split clean when you barely did more than blow on them.