In article , Carol Russell Russells@q
ueenborough42.freeserve.co.uk writes

I have been advised that elderberry doesn't throw suckers from its roots
therefore if you cut it down then sever the roots as far as you can from
the trunk it should die. This is what I have just done and will find if
its true in due course.

Yes, that will kill off most elders. You may have a small number of
coppicing shoots (not suckers) grow up from the remains of the roots.
They are easily pinched out and the rest will die off in a short while.
--
Alan & Joan Gould - North Lincs.