On 11/08/2014 20:00, Tam Inglis wrote:
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.

Glyphosate. I lopped the canes in late summer or early autumn and
poured or sprayed a little solution into the hollow centre of the
stumps. Any spindly growth that came up next year was sprayed.

Digging is not recommended. The roots go deep and if you miss a piece
it /will/ be back.
--
Phil Cook