"Tam Inglis" wrote in message
...
Hi,

I've spent the last week digging and sifting the rhizome system of an
infestation of Japanese knotweed.

however I've now come up against the fact that it is running underneath the
driveway/patio.

I thought i had caught it before it would have spread there (and indeed it
is relatively clear) however there was one 'crown' perhaps a meter at the
closest point to the patio and as a result there two main roots heading off
directly underneath the driveway and patio.

I'll take the bricks and patio slabs up if nothing else presents itself but
if anyone has any help/tips for removing/killing a root system underneath
non-diggable area it would be *greatly* appreciated.

T

Please stop digging at it, you will only make matters worse.

Either keep cutting it before it makes any leaves (make sure you burn what
you cut off, never bin it) or use Roundup type weed killer, there is plenty
of advice online as to when and how, I prefer the squirting it down the cut
stem approach, which ever way you chose remember it will take at least two
seasons and possibly 3.

--
Charlie, Gardening in Cornwall
Holders of National Collections of Clematis viticella
and Lapageria rosea cvs
http://www.roselandhouse.co.uk