On Sat, 22 Mar 2014 17:41:34 GMT, Lobster wrote:

I'm not after getting the whole thing out - if I just get the stump
below ground level and cover it with a plant tub or something, that
would be fine!

So just buy a cheap pack of three crosscut hand saws and set to with
the saws, or attack it with a splitting axe or just drive a 2" wide
bolster chisel into it an inch from the edge, split lumps off it and
work yoru way across. Might need some extra cold chisels as wedges or
get a log splitting grenade. Just takes a bit of physical effort.

--
Cheers
Dave.