I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Jeanne

"Pete" wrote in message
...
I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

I'm overwhelmed with cleavers atm. Not rosebay willowherb which will bring
you a nice hawkmoth next year if you leave it for the caterpillars now.

In article ,
says...

I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots.

Keep cutting or pulling the stems BEFORE they mature; and trample on
the RBH stem stumps. That way you will prevent new baby plants germinating
from seed, and eventually starve the RBH roots to death.

The top growth of both weeds (without seeds) is excellent green material
for the compost heap.

Janet

On May 20, 7:02*pm, Janet wrote:
In article ,
says...



I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

* Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

*RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots..

* Keep cutting or pulling the stems BEFORE they *mature; and trample on
the RBH stem stumps. That way you will prevent new baby plants germinating
from seed, and *eventually starve the RBH roots to death.

* The top growth of both weeds (without seeds) is excellent green material
for the compost heap.

* Janet

On the Great British Menue last week one of the Chefs was cooking
young Cleaver shoots.
I've yet to try.
David

On 20/05/2012 19:02, Janet wrote:
In ,
says...

I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots.

Rosebay Willow Herb is another of these curious weeds that is sometimes
absolutely rampant and a serious menace or elsewhere barely able to eke
out a living. I have never been able to figure out whether there are
different cultivars of it or some soils do not suit it. Seems to be more
likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Keep cutting or pulling the stems BEFORE they mature; and trample on
the RBH stem stumps. That way you will prevent new baby plants germinating
from seed, and eventually starve the RBH roots to death.

The top growth of both weeds (without seeds) is excellent green material
for the compost heap.

Janet


--
Regards,
Martin Brown

In message , Martin Brown
writes
On 20/05/2012 19:02, Janet wrote:
In ,
says...

I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots.

Rosebay Willow Herb is another of these curious weeds that is sometimes
absolutely rampant and a serious menace or elsewhere barely able to eke
out a living. I have never been able to figure out whether there are
different cultivars of it or some soils do not suit it. Seems to be
more likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,
and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]

In this neck of the woods Convolvulus arvensis is relatively rare. It's
less than a tenth as common as Calystegia silvatica and Calystegia
sepium, and is also rarer than Calystegia pulchra. Even black bindweed
(Fallopia convolvulus) - a weed of maize fields - is commoner

Keep cutting or pulling the stems BEFORE they mature; and trample on
the RBH stem stumps. That way you will prevent new baby plants germinating
from seed, and eventually starve the RBH roots to death.

The top growth of both weeds (without seeds) is excellent green material
for the compost heap.

Janet



--
Stewart Robert Hinsley

On Mon, 21 May 2012 13:13:31 +0100, Stewart Robert Hinsley
wrote:

In message , Martin Brown
writes
On 20/05/2012 19:02, Janet wrote:
In ,
says...

I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots.

Rosebay Willow Herb is another of these curious weeds that is sometimes
absolutely rampant and a serious menace or elsewhere barely able to eke
out a living. I have never been able to figure out whether there are
different cultivars of it or some soils do not suit it. Seems to be
more likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,
and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]


I acquired the white willow herb a few years ago but it had to go as
it spread like ;mad, but is quite beautiful if you have the space to
let it be rampant.

Pam in Bristol

In message , Pam Moore
writes
On Mon, 21 May 2012 13:13:31 +0100, Stewart Robert Hinsley
wrote:

In message , Martin Brown
writes
On 20/05/2012 19:02, Janet wrote:
In ,
says...

I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots.

Rosebay Willow Herb is another of these curious weeds that is sometimes
absolutely rampant and a serious menace or elsewhere barely able to eke
out a living. I have never been able to figure out whether there are
different cultivars of it or some soils do not suit it. Seems to be
more likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,
and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]


I acquired the white willow herb a few years ago but it had to go as
it spread like ;mad, but is quite beautiful if you have the space to
let it be rampant.

The white form is usually claimed as innocuous. The local plantsman had
it, and it was well-behaved with him.


Pam in Bristol

--
Stewart Robert Hinsley

On 21/05/2012 13:13, Stewart Robert Hinsley wrote:
In message , Martin Brown
writes

Rosebay Willow Herb is another of these curious weeds that is
sometimes absolutely rampant and a serious menace or elsewhere barely
able to eke out a living. I have never been able to figure out whether
there are different cultivars of it or some soils do not suit it.
Seems to be more likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

I have heard tell that the railways are to blame for spreading it and
also WWII bombsites. I don't know if there is any truth in either.

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,

Curiouser and curiouser.

Whatever form it is I recall that it sets copious amounts of fluffy
seeds and ISTR they were viable. It also spreads by thin underground
runners/rhizomes and is very vigorous - able to hold its own and even
win against nettles and brambles on an embankment.

and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]

Is there an easy way to tell the cytotypes apart without an oil
immersion microscope and fancy DNA stains?

I probably still have access to a sample of the weak and feeble form.

In this neck of the woods Convolvulus arvensis is relatively rare. It's

I quite like it. Doesn't grow much like a weed on heavy clay for me.

less than a tenth as common as Calystegia silvatica and Calystegia
sepium, and is also rarer than Calystegia pulchra. Even black bindweed
(Fallopia convolvulus) - a weed of maize fields - is commoner

I think local conditions play a big part although common hedge bindweed
is a potent smothering weed even in robust country hedgerows. I suspect
the ornamental ones could be a nuisance if they were winter hardy.

--
Regards,
Martin Brown

On Mon, 21 May 2012 16:04:02 +0100, Stewart Robert Hinsley
wrote:

In message , Pam Moore
writes
On Mon, 21 May 2012 13:13:31 +0100, Stewart Robert Hinsley
wrote:

In message , Martin Brown
writes
On 20/05/2012 19:02, Janet wrote:
In ,
says...

I seem to be overwhelmed by these two this year. Cleavers have always been
around in our garden (South Cheshire) but not to the extent that we have
them now and Rosebay Willow Herb has never been a problem before.

Is the weather to blame? Is there anything I can do to reduce the numbers
next year?

Cleavers are annual; they grow from seed every year then die. With any
annual weed if you prevent them re-seeding into your garden then the
population will eventually dwindle out. It's an easy weed to pull out by
hand.

RWH is perennial and can spread underground as well as by seed; the roots
survive underground in winter and regrow the next year. It also sets a LOT
of seed, so you need to both prevent it flowering, and kill off the roots.

Rosebay Willow Herb is another of these curious weeds that is sometimes
absolutely rampant and a serious menace or elsewhere barely able to eke
out a living. I have never been able to figure out whether there are
different cultivars of it or some soils do not suit it. Seems to be
more likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,
and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]


I acquired the white willow herb a few years ago but it had to go as
it spread like ;mad, but is quite beautiful if you have the space to
let it be rampant.

The white form is usually claimed as innocuous. The local plantsman had
it, and it was well-behaved with him.

I put a chunk of it on my allotment and it spread rapidly, by
underground shoots. I bought it from Derry Watkins at Special Plants,
and she warned me it could be "invasive". It was!

Pam in Bristol

In message , Martin Brown
writes
On 21/05/2012 13:13, Stewart Robert Hinsley wrote:
In message , Martin Brown
writes

Rosebay Willow Herb is another of these curious weeds that is
sometimes absolutely rampant and a serious menace or elsewhere barely
able to eke out a living. I have never been able to figure out whether
there are different cultivars of it or some soils do not suit it.
Seems to be more likely to go rampant in well drained fertile soils.

The one growing along railway lines is usually pretty rampant. But I
have seen in particularly in gardens up north with heavy clay soils
barely able to put up more than two or three shoots each season and
entirely self limiting in growth. Same for the low growing bindweed
(though not the more brutal common C. arvensis)

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

I have heard tell that the railways are to blame for spreading it and
also WWII bombsites. I don't know if there is any truth in either.

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,

Curiouser and curiouser.

Whatever form it is I recall that it sets copious amounts of fluffy
seeds and ISTR they were viable. It also spreads by thin underground
runners/rhizomes and is very vigorous - able to hold its own and even
win against nettles and brambles on an embankment.

and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]

Is there an easy way to tell the cytotypes apart without an oil
immersion microscope and fancy DNA stains?

Not to my knowledge. I presume that flow densitometry doesn't count as
an easier alternative to counting chromosomes.

I probably still have access to a sample of the weak and feeble form.

In this neck of the woods Convolvulus arvensis is relatively rare. It's

I quite like it. Doesn't grow much like a weed on heavy clay for me.

less than a tenth as common as Calystegia silvatica and Calystegia
sepium, and is also rarer than Calystegia pulchra. Even black bindweed
(Fallopia convolvulus) - a weed of maize fields - is commoner

I think local conditions play a big part although common hedge bindweed
is a potent smothering weed even in robust country hedgerows. I suspect
the ornamental ones could be a nuisance if they were winter hardy.


--
Stewart Robert Hinsley

In article ,
Martin Brown wrote:
On 21/05/2012 13:13, Stewart Robert Hinsley wrote:
In message , Martin Brown
writes

Rosebay Willow Herb is another of these curious weeds that is
sometimes absolutely rampant and a serious menace or elsewhere barely
able to eke out a living. I have never been able to figure out whether
there are different cultivars of it or some soils do not suit it.
Seems to be more likely to go rampant in well drained fertile soils.

Actually, most weeds are like that. The reason that the UK has so
many that are ubiquitous is that the populated parts of the UK have
a very narrow range of climate and pretty similar soil types. But,
even here, there are only a minority that are a problem everywhere.

Supposedly in the 19th century rosebay willowherb was an innocuous
plant, and it didn't become invasive until the 20th century.

I have heard tell that the railways are to blame for spreading it and
also WWII bombsites. I don't know if there is any truth in either.

The former, almost certainly, much as with buddleia, by providing
suitable corridors. But it grew in the latter merely because it
is a fairly dominant weed of exposed, poor soils (such as rubble!)
It might have spread it around London, but most of the country had
very sparse bombsites.

I doubt that any more is known about why plants suddenly become
invasive than why animals do. For those, I mention merely the
norwegian rat, the rabbit and the collared dove - of those, I have
heard plausible but unproven explanations of the last, and know
of none of the first two (though I haven't looked hard).

There are three cytotypes - Chamaerion angustifolium (diploid),
Chamaerion platyphyllum (tetraploid) and Chamaerion danielsii
(hexaploid). I wonder whether it's just one of them which is invasive,

and that this one wasn't present in Britain (much) before the 20th
century. [British botanists don't make a distinction between the
cytotypes.]

That wouldn't be a first time!


Regards,
Nick Maclaren.

wrote in message ...
writes
and the collared dove - of those, I have
heard plausible but unproven explanations of the last, and know
of none of the first two (though I haven't looked hard).

Having a sparrowhawk here has reduced my collared dove population to nil.
Tina

On Sun, 27 May 2012 18:00:30 +0100, "Christina Websell"
wrote:


wrote in message ...
writes
and the collared dove - of those, I have
heard plausible but unproven explanations of the last, and know
of none of the first two (though I haven't looked hard).

Having a sparrowhawk here has reduced my collared dove population to nil.
Tina

Interesting as here, despite a few sparrow hawks (I say a few thanks
to simultaneous sightings) and buzzards flying a bit higher but
swooping down occasionally, the collared dove population has trebled
to 3 pairs this year (they have occasionally arrived together). They
seem very brave and don't stop feeding if we or cat walk out into the
garden but they do get aggressive if smaller birds try to get at the
bird table when they're on it.

Cheers, Jake
=======================================
Urgling from the asylum formerly known as the
dry end of Swansea Bay.

In article ,
lid says...

On Sun, 27 May 2012 18:00:30 +0100, "Christina Websell"
wrote:


wrote in message ...
writes
and the collared dove - of those, I have
heard plausible but unproven explanations of the last, and know
of none of the first two (though I haven't looked hard).

Having a sparrowhawk here has reduced my collared dove population to nil.
Tina

Interesting as here, despite a few sparrow hawks (I say a few thanks
to simultaneous sightings) and buzzards flying a bit higher but
swooping down occasionally, the collared dove population has trebled
to 3 pairs this year (they have occasionally arrived together). They
seem very brave and don't stop feeding if we or cat walk out into the
garden but they do get aggressive if smaller birds try to get at the
bird table when they're on it.

Same experience here; the collar doves are slowly increasing despite the
sparrow hawks. I only ever see one sparrow hawk at a time to hard to tell
what their population is doing.

Janet