wrote on Oct 7^th, 2012 at 9:56am:

Hydraulic log splitter on a tractor is probably the best way then. Bruixot

"Splitting" is fine whether using a big hydraulic rig (and it would have to be big as some of these beasts are about 1.5m across) or wedges and a sledge hammer (I've already done a bit of this) if the timber has a grain, which these roots don't.
I've been looking at screw cones.  See here:- http://www.youtube.com/watch?v=-96llukCoH8
This guy's cone is too small (shut up Av) and he's spinning it too fast.  The right size and speed and he wouldn't have to reverse the tractor.  The cone would pull the lumps onto itself and they wouldn't be smoking.  However, I'd settle for that if a) there was someone available locally and b) they weren't gonna charge me more than the end product is worth.  I could buy a cone and try to turn it by hand (with a very long lever) but it would still be hard work and time consuming/