"Martin" wrote
You can buy a membrane that is opaque, but water permeable. Using this it
takes
at least a year to kill the couch grass under the cover. You need to kill
the
couch grass on a strip of land along the edge of the cover first otherwise
the
couch grass under the edge of the membrane grows outwards towards the
light.
Use glyphosate while you can, before it is banned. From 1 January 2015 in
the
Netherlands there will be a ban on the use of glyphosate, except for
agriculture. In particular local authorities and private individuals are
banned
from buying and using it. It was found that glyphosate applied to roads and
pavements by local authorities was sometimes being washed down the drains
by
rain before it had time to break down.

That is not a problem with the chemical it's a problem with the use so why
ban it, just stipulate where/when it can/can't be used by local authorities
(No hard surfaces for example), makes no sense and forces users to resort to
much worse and long lasting chemicals. I bet they haven't considered what
the alternative is.
Sometimes I despair of those in authority.
--
Regards. Bob Hobden.
Posted to this Newsgroup from the W of London, UK