with lots of effort
you can rot them with some preparation from garden centre but to get them out quickly its an axe and a spade and maybe a pint of beer or glass of wine after lol
well thats the only way I knowunless you have enough room for a digger
Sorry:)

drill holes in the top of the stump as large as you can, and near to the edge, fill the holes with SBK, brushwood killer. from the garden center about £7.50, cover and leave for a couple of months, then try to rock it when it is ready it will come out like a loose tooth, forget the roots they are dead and will rot away.

Drill holes as Cliffo says near the cambrian layer, with at least a half inch drill, pour in neat SBK till the holes are almost full, plug the top of the holes with putty. It will take up to 12 months for the tree to die and rot. If you want to see the result of a very large Cherry treated five years ago, look at my photos.

the photo explains every thing,nice one Doc'

If you can get a JCB in, then that is the easiest way.

I understood stump killer only works if applied in the first 48 hours after felling?
What about a stump grinder?

I used stump killer but it didnt work very fast we ended up digging it up
the hard way 2 years later!!! it was a biggish tree and maybe we didnt do it right ?