Could someone kindly identify this plant we came across on a recent walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Terry, East Grinstead, UK

On 13/09/2019 20:35, Terry Pinnell wrote:
Could someone kindly identify this plant we came across on a recent walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Terry, East Grinstead, UK


Looks like one of the Gunneras - aka Giant Rhubarb ..?

On 13/09/2019 20:35, Terry Pinnell wrote:
Could someone kindly identify this plant we came across on a recent walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Terry, East Grinstead, UK


Gunnera manicata

On 13/09/2019 20:55, David Hill wrote:
On 13/09/2019 20:35, Terry Pinnell wrote:
Could someone kindly identify this plant we came across on a recent
walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Terry, East Grinstead, UK


Gunnera manicata

I think it may have been banned from sale? due to the number of garden
escapees!

--
Charlie Pridham
Gardening in Cornwall
www.roselandhouse.co.uk

On 14/09/2019 11:31, Charlie Pridham wrote:
On 13/09/2019 20:55, David Hill wrote:
On 13/09/2019 20:35, Terry Pinnell wrote:
Could someone kindly identify this plant we came across on a recent
walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Terry, East Grinstead, UK


Gunnera manicata

I think it may have been banned from sale? due to the number of garden
escapees!


Gunnera is an invasive plant in the west of Ireland and the Outer
Hebrides (possibly also Kintyre and Knapdale - someone reported seeing
lots around there as well).

--
SRH

Terry Pinnell wrote:

Could someone kindly identify this plant we came across on a recent walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Terry, East Grinstead, UK

Thanks all.

Terry, East Grinstead, UK

In article ,
Stewart Robert Hinsley wrote:
On 14/09/2019 11:31, Charlie Pridham wrote:
On 13/09/2019 20:55, David Hill wrote:
On 13/09/2019 20:35, Terry Pinnell wrote:
Could someone kindly identify this plant we came across on a recent
walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Gunnera manicata

I think it may have been banned from sale? due to the number of garden
escapees!

Not in the UK, it hasn't been. It's widely available.

Gunnera is an invasive plant in the west of Ireland and the Outer
Hebrides (possibly also Kintyre and Knapdale - someone reported seeing
lots around there as well).

On the other hand, almost all of the ecologies of the British Isles
are comprised entirely of recently invasive plants! Other than
Japanese knotweed (and, just possibly, Rhododendron ponticum in a
FEW locations), no recent introduction of land plants seems capable of
forming monocultures (the main ecological problem). It's a jungle out
there :-)


Regards,
Nick Maclaren.

On 14/09/2019 19:49, Nick Maclaren wrote:
In article ,
Stewart Robert Hinsley wrote:
On 14/09/2019 11:31, Charlie Pridham wrote:
On 13/09/2019 20:55, David Hill wrote:
On 13/09/2019 20:35, Terry Pinnell wrote:
Could someone kindly identify this plant we came across on a recent
walk in South
Cornwall please?

https://www.dropbox.com/s/cft2kqjt8k...lant.jpg?raw=1

Gunnera manicata

I think it may have been banned from sale? due to the number of garden
escapees!

Not in the UK, it hasn't been. It's widely available.

It is still available but they are having a bit of bother with it
escaping in the milder areas of western Scotland. Logan botanical
gardens has an impressive stand of the stuff that must be about 100m
square with a path through the middle. It looks primaeval.

Gunnera is an invasive plant in the west of Ireland and the Outer
Hebrides (possibly also Kintyre and Knapdale - someone reported seeing
lots around there as well).

On the other hand, almost all of the ecologies of the British Isles
are comprised entirely of recently invasive plants! Other than
Japanese knotweed (and, just possibly, Rhododendron ponticum in a
FEW locations), no recent introduction of land plants seems capable of
forming monocultures (the main ecological problem). It's a jungle out
there :-)

Himalayan balsam is becoming quite a problem in North Yorkshire on
stream and river banks wiping out almost everything else and spreading
rapidly. Only Japanese knotweed out competes it. Nettles and rosebay
willow herb both die out after a few years leaving a monoculture.

--
Regards,
Martin Brown

In article ,
Martin Brown wrote:

Himalayan balsam is becoming quite a problem in North Yorkshire on
stream and river banks wiping out almost everything else and spreading
rapidly. Only Japanese knotweed out competes it. Nettles and rosebay
willow herb both die out after a few years leaving a monoculture.

I have never seen it do that, and I have been looking out for it for
several decades now. I believe you that it is a (very) localised
problem, but it assuredly isn't a widespread one. Every apparent
monoculture of it I have looked at has turned out to be, on closer
inspection, merely that it dominates the top layer and there is a
wide range of other species underneath it.


Regards,
Nick Maclaren.

On Mon, 16 Sep 2019 12:10:50 Nick Maclaren wrote:

In article ,
Martin Brown wrote:

Himalayan balsam is becoming quite a problem in North Yorkshire on
stream and river banks wiping out almost everything else and spreading
rapidly. Only Japanese knotweed out competes it. Nettles and rosebay
willow herb both die out after a few years leaving a monoculture.

I have never seen it do that, and I have been looking out for it for
several decades now. I believe you that it is a (very) localised
problem, but it assuredly isn't a widespread one. Every apparent
monoculture of it I have looked at has turned out to be, on closer
inspection, merely that it dominates the top layer and there is a
wide range of other species underneath it.

Interesting about rosebay willowherb (or should it be rose bay willow
herb? - I've never been sure). I remember my father pointing out to me
the way that it colonised bomb sites during the second world war
especially in London. Then for most of my life it seemed to have
disappeared only to reappear in the last few years, and for the first
time I have some springing up in my garden.

David

--
David Rance writing from Caversham, Reading, UK

On 16/09/2019 17:59, David Rance wrote:
On Mon, 16 Sep 2019 12:10:50 Nick Maclaren wrote:

In article ,
Martin BrownÂ* wrote:

Himalayan balsam is becoming quite a problem in North Yorkshire on
stream and river banks wiping out almost everything else and spreading
rapidly. Only Japanese knotweed out competes it. Nettles and rosebay
willow herb both die out after a few years leaving a monoculture.

I have never seen it do that, and I have been looking out for it for
several decades now.Â* I believe you that it is a (very) localised
problem, but it assuredly isn't a widespread one.Â* Every apparent

I can well believe that it is only a local difficulty, but it seems to
be incredibly effective at moving along water courses and colonising the
banks to the near exclusion of everything else unless treated promptly.
Its flowers smell quite nice in the evenings a bit like bizzy lizzies on
steroids the explosive seed capsules pack more of a punch.

monoculture of it I have looked at has turned out to be, on closer
inspection, merely that it dominates the top layer and there is a
wide range of other species underneath it.

Only if you count grasses which do seem to hang on in the margins.

Interesting about rosebay willowherb (or should it be rose bay willow
herb? - I've never been sure). I remember my father pointing out to me
the way that it colonised bomb sites during the second world war
especially in London. Then for most of my life it seemed to have
disappeared only to reappear in the last few years, and for the first
time I have some springing up in my garden.

I remember the rosebay willow herb of my youth being a much more
vigorous invasive weed in Manchester on a sandy soil. On my North
Yorkshire heavy clay it barely survives and is seldom seen in hedgerows
here except on or near railway enbankments.

Are there multiple sorts or is it very sensitive to local conditions?

--
Regards,
Martin Brown

Someone told me of apps to identify plants.
http://bestappsguru.com/best-plant-identification-app/ grades some. No
experience of them, but having cultivated a plant I thought was a foxglove
with no flowers for two years, I am tempted to try it.

On 16/09/2019 18:33, Martin Brown wrote:
On 16/09/2019 17:59, David Rance wrote:
On Mon, 16 Sep 2019 12:10:50 Nick Maclaren wrote:

In article ,
Martin BrownÂ* wrote:

Himalayan balsam is becoming quite a problem in North Yorkshire on
stream and river banks wiping out almost everything else and spreading
rapidly. Only Japanese knotweed out competes it. Nettles and rosebay
willow herb both die out after a few years leaving a monoculture.

I have never seen it do that, and I have been looking out for it for
several decades now.Â* I believe you that it is a (very) localised
problem, but it assuredly isn't a widespread one.Â* Every apparent

I can well believe that it is only a local difficulty, but it seems to
be incredibly effective at moving along water courses and colonising the
banks to the near exclusion of everything else unless treated promptly.
Its flowers smell quite nice in the evenings a bit like bizzy lizzies on
steroids the explosive seed capsules pack more of a punch.

monoculture of it I have looked at has turned out to be, on closer
inspection, merely that it dominates the top layer and there is a
wide range of other species underneath it.

Only if you count grasses which do seem to hang on in the margins.

Interesting about rosebay willowherb (or should it be rose bay willow
herb? - I've never been sure). I remember my father pointing out to me
the way that it colonised bomb sites during the second world war
especially in London. Then for most of my life it seemed to have
disappeared only to reappear in the last few years, and for the first
time I have some springing up in my garden.

I remember the rosebay willow herb of my youth being a much more
vigorous invasive weed in Manchester on a sandy soil. On my North
Yorkshire heavy clay it barely survives and is seldom seen in hedgerows
here except on or near railway enbankments.

Are there multiple sorts or is it very sensitive to local conditions?


The genus has 8 recognised species, but only one is in the British
Flora. (A second species occurs as a rare garden escape.) However in
North America at least there are two cytotypes (cryptic species) of
Chamaenerion angustifolium, with mostly disjunct distributions.
Supposedly it was a relatively rare plant prior to WWII, and became
somewhat invasive afterwards. I wonder whether a non-native strain was
introduced.

It's my 24th most recorded plant, coming in behind Dryopteris filix-mas
and Senecio vulgaris, and ahead of Epilobium hirsutum.

In article ,
Stewart Robert Hinsley wrote:
On 16/09/2019 18:33, Martin Brown wrote:

I remember the rosebay willow herb of my youth being a much more
vigorous invasive weed in Manchester on a sandy soil. On my North
Yorkshire heavy clay it barely survives and is seldom seen in hedgerows
here except on or near railway enbankments.

Yes. It's definitely a plant of well-drained soils.

Are there multiple sorts or is it very sensitive to local conditions?

The genus has 8 recognised species, but only one is in the British
Flora. (A second species occurs as a rare garden escape.) However in
North America at least there are two cytotypes (cryptic species) of
Chamaenerion angustifolium, with mostly disjunct distributions.
Supposedly it was a relatively rare plant prior to WWII, and became
somewhat invasive afterwards. I wonder whether a non-native strain was
introduced.

As I was born in a far country in 1947, I cannot say :-) But my
definite recollection is that it because far more widespread in the
1960s and 1970s. That is a very plausible hypothesis.


Regards,
Nick Maclaren.

On 16/09/19 21:58, Nick Maclaren wrote:
In article ,
Stewart Robert Hinsley wrote:
On 16/09/2019 18:33, Martin Brown wrote:

I remember the rosebay willow herb of my youth being a much more
vigorous invasive weed in Manchester on a sandy soil. On my North
Yorkshire heavy clay it barely survives and is seldom seen in hedgerows
here except on or near railway enbankments.

Yes. It's definitely a plant of well-drained soils.

I remember it being particularly prevalent in the central reservation
strip of dual carriageways. Even there it would be quite localised,
covering maybe a hundred meters but with nothing for several km either side.

Mind you, it is possible to get very odd things growing in central
reservations. Maybe 20 years ago on the m25 south of Heathrow there
were, over about 50 metres, dozens of giant puffballs!

--

Jeff