"Nick Maclaren" wrote in message
...

In article ,
"Rupert \(W.Yorkshire\)" writes:
|
| I grow reasonable clumps of ivy broomrape (orobanche hederae) on the
| ivy growing on some of my trees. Its a root parasite of ivy.
| You don't actually see anything until it flowers - when it looks like
| some kind of orchid. Seed from Chiltern.
|
| John that's going to cost me money Chiltern here I come. I've had a
look
| at the description and it sounds like it grows in the ground as tubers?
| I assume from what you say that it can be treated as an epiphytic type
| thing way up in the branches of an ivy clad tree.

No, it's a root parasite. It builds tubers from what it takes from the
roots, and the flowers arise from those - according to CTW.


Regards,
Nick Maclaren.

Thanks Nick for bringing me back to earth. I was equating the tendrils with
roots. Looks like I will have to stuff a pot of ivy up the tree:-)

"John McMillan" wrote in message
...
In article ,
Sacha wrote:

On 9/1/07 17:41, in article ,
"Eric L
Drever" wrote:

I have just acquired a garden with some big, established trees. They
have a lot of ivy growing up them. I have asked friends whether I
should leave this or remove it, and so far have had two responses:

1 Ivy isn't a parasite and doesn't do the trees any harm, so leave
it.

2 Ivy may not be a parasite but the weight of it is bad for the
trees,
and it isn't doing them any good, so get rid of it.

My friends are now hardly on speaking terms. Who is right?

AFAIK, it doesn't do the trees any harm but in big gales, such as we are
having now, the windage of the ivy on a leafless tree will still act as a
sail and might bring the tree down. Personally, I'd be rid of it on most
trees and perhaps leave it on one or two that are more sheltered or about
which you're less concerned.

Another point to consider is that a tree without ivy will shade the
ground to some extent. A tree covered with ivy will normally be much
denser and bigger than the original tree and the shade will be deeper.
If you like gardening in dry shade then thats fine.

I grow reasonable clumps of ivy broomrape (orobanche hederae) on the
ivy growing on some of my trees. Its a root parasite of ivy.
You don't actually see anything until it flowers - when it looks like
some kind of orchid. Seed from Chiltern.

Kewl!!!! Was it easy to grow??

Des in Dublin

The message
from Eric L Drever contains these words:

I have just acquired a garden with some big, established trees. They
have a lot of ivy growing up them. I have asked friends whether I
should leave this or remove it, and so far have had two responses

Well, now I have had a lot of responses. Thanks to everyone who replied.
I will probably have to remove one of the trees anyway; otherwise I
shall trim the excessive areas of ivy, and keep watch on what lives in
the rest. Also, I may get some of the ivy broomrape!

Thanks again.
ELD

Eric L Drever wrote:
The message
from Eric L Drever contains these words:

I have just acquired a garden with some big, established trees. They
have a lot of ivy growing up them. I have asked friends whether I
should leave this or remove it, and so far have had two responses

Well, now I have had a lot of responses. Thanks to everyone who replied.
I will probably have to remove one of the trees anyway; otherwise I
shall trim the excessive areas of ivy, and keep watch on what lives in
the rest. Also, I may get some of the ivy broomrape!


Just to add to what Nick said about ivy dominating the canopy. In
general, wild forms of the native ivy (H.Helix) don't seem to get big
enough to do that to the bigger native trees -- I had several oaks of
varying age, most of which had healthy ivies in residence and suffered
no ill effect.

In that garden I had a mania for collecting different ivies and growing
them all over the place. What I did notice was what a very
mild-mannered little variegated form, "Hester", did to a single white
flowering cherry (variety unknown). This tree was in a marginal
situation, on poor soil only a short way above the winter water table.
It grew well enough; but I let the ivy cover the lower branches, and it
clearly seemed to shade the tree's own foliage to death. So I'd relax
about ivy in big established trees, but keep all forms away from
anything small or sensitive, or in a dodgy position.

Next week: how a thoughtless fondness for orange hawkweed nearly caused
the disintegration of a fine mind.

--
Mike.

"Eric L Drever" wrote in message
...
The message
from Eric L Drever contains these words:

I have just acquired a garden with some big, established trees. They
have a lot of ivy growing up them. I have asked friends whether I
should leave this or remove it, and so far have had two responses

Well, now I have had a lot of responses. Thanks to everyone who replied.
I will probably have to remove one of the trees anyway; otherwise I
shall trim the excessive areas of ivy, and keep watch on what lives in
the rest. Also, I may get some of the ivy broomrape!

I've just remembered that I've got ivy growing on a couple of my apple
trees, I've tried, not very sucessfully, to get rid of it.

Alan

In article ,
(Nick Maclaren) wrote:

In article ,
"Rupert \(W.Yorkshire\)" writes:
|
| I grow reasonable clumps of ivy broomrape (orobanche hederae) on the
| ivy growing on some of my trees. Its a root parasite of ivy.
| You don't actually see anything until it flowers - when it looks like
| some kind of orchid. Seed from Chiltern.
|
| John that's going to cost me money Chiltern here I come. I've had a look
| at the description and it sounds like it grows in the ground as tubers?
| I assume from what you say that it can be treated as an epiphytic type
| thing way up in the branches of an ivy clad tree.

No, it's a root parasite. It builds tubers from what it takes from the
roots, and the flowers arise from those - according to CTW.


Definitely a root parasite. If you gently dig near the flowers there
are tubers/haustoria about the size of small new potatoes.

Kewl!!!! Was it easy to grow??

Stunningly easy, though you need patience.
I bought a packet (or two, forget now) of seed from
Chiltern. It was fine-ish so I probably mixed it with a bit of
fine dry sand so I could see what I was doing. Dug round the roots
of the ivy till I exposed some fibrous roots and sprinkled the seed
sand mix in. Covered it up and forgot about it. Assumed it didn't
work. A couple of years later I noticed these odd looking pinky brown
flower spikes round the base of the ivy in summer. Later in the year
the flower spikes had dried - and hey guess what, more seed.
So now I've managed to develop three or four colonies around my site
and maybe more are busy developing underground.
Sadly, it appears to have no impact whatever on the vigour of the ivy.

Having said that, I have talked to other people who've tried it with no
success at all. Maybe it particularly likes my soil/site which is
free draining 10cm soil on a rubble base at an incline of thirty degrees.

If you put "orobanche hederae" into google images you'll get lots of
pictures. When I said they were like orchids I meant things like common
spotted orchid rather than those huge garish things that live on trees
in jungles.

Flushed by the success with this, I've also tried Purple Toothwort
(Lathraea clandestina) on the roots of goat willow - without any
sign of success yet. It grows at a number of sites within 50km of me
so it should be OK. RHS Hyde Hall
http://www.rhs.org.uk/WhatsOn/garden...hallpom04apr.a
sp have the useful tip; -
"This is not the plant of choice for instant effect in the garden as it
is sometimes 10 years before a flowering shoot emerges above the ground."

Alan Holmes wrote:
[...]
I've just remembered that I've got ivy growing on a couple of my apple
trees, I've tried, not very sucessfully, to get rid of it.

Interesting. Did you try very hard? I'm imagining a grassed-down apple
tree, where the ivy's very shallow roots would be quite hard to get
out, or where the apple's feeding roots were very near the surface; but
in clear soil I've found they come out pretty well. I can't remember
your position on chemicals; but how about cutting off, and painting the
stumps with something nasty? (I don't like it, but I've done that a few
times with neat SBK where there really was no way to get a bramble or
tree seedling right out without disturbing something cherished.)

--
Mike.

In article .com,
"Mike Lyle" wrote:

Alan Holmes wrote:
[...]
I've just remembered that I've got ivy growing on a couple of my apple
trees, I've tried, not very sucessfully, to get rid of it.

Interesting. Did you try very hard? I'm imagining a grassed-down apple
tree, where the ivy's very shallow roots would be quite hard to get
out, or where the apple's feeding roots were very near the surface; but
in clear soil I've found they come out pretty well. I can't remember
your position on chemicals; but how about cutting off, and painting the
stumps with something nasty? (I don't like it, but I've done that a few
times with neat SBK where there really was no way to get a bramble or
tree seedling right out without disturbing something cherished.)

When I'm not hosting root parasites on ivy, I try to kill it.
I have to admit I have an awful lot of ivy and I've only removed
about a tenth of it yet. My technique is to cut through the
bigger stems with loppers and remove all the upper foliage
I can get to. Its utterly impossible to remove all the roots
since they go deep into rocky, rubbly soil, through walls etc etc.
I wait until there's some regrowth then I paint the leaves with
a mix of roundup, wallpaper paste and washing up liquid. The idea
is that the ivy leaves are waxy and spray just runs off. Then
I wait until it has a second go at regrowing and repeat. This seems
to work, even if it is a bit labour intensive. Has anyone got
a better idea.

"John McMillan" wrote in message
...
In article ,
small new potatoes.

Kewl!!!! Was it easy to grow??

Stunningly easy, though you need patience.
I bought a packet (or two, forget now) of seed from
Chiltern. It was fine-ish so I probably mixed it with a bit of
fine dry sand so I could see what I was doing. Dug round the roots
of the ivy till I exposed some fibrous roots and sprinkled the seed
sand mix in. Covered it up and forgot about it. Assumed it didn't
work. A couple of years later I noticed these odd looking pinky brown
flower spikes round the base of the ivy in summer. Later in the year
the flower spikes had dried - and hey guess what, more seed.
So now I've managed to develop three or four colonies around my site
and maybe more are busy developing underground.
Sadly, it appears to have no impact whatever on the vigour of the ivy.


Wow! Well done that man. They are pretty when the flowers are fresh.

Having said that, I have talked to other people who've tried it with no
success at all. Maybe it particularly likes my soil/site which is
free draining 10cm soil on a rubble base at an incline of thirty degrees.

If you put "orobanche hederae" into google images you'll get lots of
pictures. When I said they were like orchids I meant things like common
spotted orchid rather than those huge garish things that live on trees
in jungles.

Flushed by the success with this, I've also tried Purple Toothwort
(Lathraea clandestina) on the roots of goat willow - without any
sign of success yet. It grows at a number of sites within 50km of me
so it should be OK. RHS Hyde Hall

I have seen wild Lathraea squamaria (native) a few times and it is nice. I
saw L.clandestine once in teh Dublin botanic gardens where it was presumably
introduced. I vaguely remember it as being fairly bright pink and small.
It would make a very good converstaion piece (all that lack of chlorophyl
and parasitism business).

Thanks for the information about the broomrape; I will add it to my list of
things to try.

http://www.rhs.org.uk/WhatsOn/garden...hallpom04apr.a
sp have the useful tip; -
"This is not the plant of choice for instant effect in the garden as it
is sometimes 10 years before a flowering shoot emerges above the ground."