I wrote this about bindweed, *but I could be wrong of course*:

the roots are extremely fragile and snap at the slightest
| opportunity. The only saving grace is it is distinctive, waxy white and
| curling, with purple tips as it breaks through the ground. If I pick any
| with newly broken ends, then I keep digging until I find the other end.
| In early march I followed one set down under the plum tree until I had
| made a rabbit burrow an arms length deep - but I think I got it all out.
| I let them dry out and then burn them.

And AIUI this stuff is brighter green, has very long above ground shoots
with purple stems, can climb itself 2-3m into trees and be very very
quick to smother almost anything (one book says 25 sq m in a season,
which would be spot on). It binds very tightly round anything and cannot
be unwound, but needs several attempts to break the stems and pull them
off. The roots are off-white, ivory, waxy, generally complex but without
root hairs, and usually curled and relatively fat. Has long arrow-shaped
leaves and white flowers. Page 282 of Collins Complete British Wildlife
shows what I understand to be it, both Field Bindweed and Hedge
varieties.
|
| Ground elder unfortunately has tiny thin roots which go straight down
| metres. I don't know how I will tackle this, except by topping and maybe
| roundup.

AIUI this stuff is more bluey-green, with smaller leaves and smaller
flowers, thinner stems which can generally be pulled out of whatever its
climbing into, and which appear as generally shorter multiple shoots off
one common ground-root, and the roots are browny and consistently thin
and apart from having a few coils near the surface they then descend
very deep indeed. Unfortunately the collins guide shows something
completely unlike what I know as ground elder :-( It is possible I am
calling this by the wrong name, and I have in fact two varieties of the
same thing, this one possibly being called 'small bindweed' according to
other books which are not very clear.

Nick Maclaren writes
Er, it's the other way round! Ground elder is very shallow rooted,
bindweed goes down metres.

Maybe I have my wires crossed? I may be able to send photos in a while -
I have just seen shoots of both growing out :-((. It would be nice to
find out.
--
David