On 09/07/2016 13:38, Janet wrote:
In article ,
says...

On Sat, 09 Jul 2016 08:07:37 +0100, Chris Hogg wrote:

On Fri, 8 Jul 2016 22:30:48 +0100, Big Les Wade wrote:

Spider posted

Sorry to rant at you, Stephen, but you really must get rid of that
knotweed before you regret it.


Doesn't glyphosate do it?

ISTR that the best way to treat it is, as you say, with glyphosate, but
specifically towards the end of the summer or early autumn, cut it off
at about 3 ft, and pour a half-strength glyphosate solution into the
hollow stems. The glyphosate is then slowly absorbed and taken down into
the root as the plant dies back in the autumn, never to emerge in the
spring.

It will take a couple of years of treatment to fully eradicate though so
don't expect to get it all in one go.

I daily drove past a 'colony' and watched as it was treated for, aprox, 3
years before it was completely eliminated. Its tough stuff!

Our local council has been spraying several local colonies of JKW for
several yesrs. You can see the deadly effect every time they treat it,
but the next year it rises from the grave again.

AFAIK, in the UK climate JKW does not propagate by seed; so a
colony's survival after weedkilling is not down to seed germination; it
reflects the depth, extent and vigour of its root systems.

My understanding is that the reason for a lack of seed propagation is
not the climate but that the plants are (nearly?) all female, so they
never (hardly ever) get pollinated. You do get hybrids with Russian vine
and giant knotweed.

But it's remarkably widespread for a plant that doesn't propagate by seed.

Janet



Janet

On 11/07/2016 23:10, Stewart Robert Hinsley wrote:
On 09/07/2016 13:38, Janet wrote:
In article ,
says...



It will take a couple of years of treatment to fully eradicate though so
don't expect to get it all in one go.

I daily drove past a 'colony' and watched as it was treated for,
aprox, 3
years before it was completely eliminated. Its tough stuff!

Our local council has been spraying several local colonies of JKW for
several yesrs. You can see the deadly effect every time they treat it,
but the next year it rises from the grave again.

AFAIK, in the UK climate JKW does not propagate by seed; so a
colony's survival after weedkilling is not down to seed germination; it
reflects the depth, extent and vigour of its root systems.

My understanding is that the reason for a lack of seed propagation is
not the climate but that the plants are (nearly?) all female, so they
never (hardly ever) get pollinated. You do get hybrids with Russian vine
and giant knotweed.

But it's remarkably widespread for a plant that doesn't propagate by seed.

Janet



Janet



It is remarkable how small a piece will regrow, even the mush on a
strimmer will produce viable plants if put in a nice spot!

It has become a much bigger problem down here once they started getting
excited about it and lenders not giving mortgages etc, people panic, try
and dig it up and fly tip it.

Weed killer and persistence is the way to go

--
Charlie Pridham, Gardening in Cornwall
www.roselandhouse.co.uk
National collections of Clematis viticella & Lapageria rosea

In article ,
says...

On 09/07/2016 13:38, Janet wrote:
In article ,
says...

On Sat, 09 Jul 2016 08:07:37 +0100, Chris Hogg wrote:

On Fri, 8 Jul 2016 22:30:48 +0100, Big Les Wade wrote:

Spider posted

Sorry to rant at you, Stephen, but you really must get rid of that
knotweed before you regret it.


Doesn't glyphosate do it?

ISTR that the best way to treat it is, as you say, with glyphosate, but
specifically towards the end of the summer or early autumn, cut it off
at about 3 ft, and pour a half-strength glyphosate solution into the
hollow stems. The glyphosate is then slowly absorbed and taken down into
the root as the plant dies back in the autumn, never to emerge in the
spring.

It will take a couple of years of treatment to fully eradicate though so
don't expect to get it all in one go.

I daily drove past a 'colony' and watched as it was treated for, aprox, 3
years before it was completely eliminated. Its tough stuff!

Our local council has been spraying several local colonies of JKW for
several yesrs. You can see the deadly effect every time they treat it,
but the next year it rises from the grave again.

AFAIK, in the UK climate JKW does not propagate by seed; so a
colony's survival after weedkilling is not down to seed germination; it
reflects the depth, extent and vigour of its root systems.

My understanding is that the reason for a lack of seed propagation is
not the climate but that the plants are (nearly?) all female, so they
never (hardly ever) get pollinated. You do get hybrids with Russian vine
and giant knotweed.

What a nightmare plant that hybrid must be :-) Mile a minute
knotweed , doersn't bear thinking about.

But it's remarkably widespread for a plant that doesn't propagate by seed.

Janet

On 12/07/2016 00:58, Janet wrote:
In article ,
says...

On 09/07/2016 13:38, Janet wrote:
In article ,
says...

On Sat, 09 Jul 2016 08:07:37 +0100, Chris Hogg wrote:

On Fri, 8 Jul 2016 22:30:48 +0100, Big Les Wade wrote:

Spider posted

Sorry to rant at you, Stephen, but you really must get rid of that
knotweed before you regret it.


Doesn't glyphosate do it?

ISTR that the best way to treat it is, as you say, with glyphosate, but
specifically towards the end of the summer or early autumn, cut it off
at about 3 ft, and pour a half-strength glyphosate solution into the
hollow stems. The glyphosate is then slowly absorbed and taken down into
the root as the plant dies back in the autumn, never to emerge in the
spring.

It will take a couple of years of treatment to fully eradicate though so
don't expect to get it all in one go.

I daily drove past a 'colony' and watched as it was treated for, aprox, 3
years before it was completely eliminated. Its tough stuff!

Our local council has been spraying several local colonies of JKW for
several yesrs. You can see the deadly effect every time they treat it,
but the next year it rises from the grave again.

AFAIK, in the UK climate JKW does not propagate by seed; so a
colony's survival after weedkilling is not down to seed germination; it
reflects the depth, extent and vigour of its root systems.

My understanding is that the reason for a lack of seed propagation is
not the climate but that the plants are (nearly?) all female, so they
never (hardly ever) get pollinated. You do get hybrids with Russian vine
and giant knotweed.

What a nightmare plant that hybrid must be :-) Mile a minute
knotweed , doersn't bear thinking about.


Well, I don't believe the Mile a Minute tag: 60 miles an hour?!! I've
walked past it and never seen it so much as twitch. Unless it's moving
so fast I can't actually see it, of course, but I suspect that's faster
than 60mph.
Let's just hope we never see that particular hybrid.


But it's remarkably widespread for a plant that doesn't propagate by seed.

Janet

--
Spider
On high ground in SE London
Gardening on heavy clay