This is the problem.
An ash tree growing tight alongside the buttress of an old building.
The trunk is about 10" dia.
We have cut the tree down, and limbs off, as far as possible in the hope
that it would gracefully die.
It still makes very robust shoots and this is the 6th season of our trying
to be rid of it.
The current plot is to drill holes in the trunk and insert poison of some
kind.
I am normally against anything of this kind but the tree has to go.
Any suggestions please on what poison might be effective?

Thanks,
Nicholas.