I have read that glyphosate is deactivated when it comes into contact
with the soil. Does that mean that you can spray weeds with glyphosate
one week and then safely plant shrubs in the same area of land a few
weeks later without there being any fears of the glyphosate which was
originally used?

Thanks,
Emrys Davies

Emrys Davies wrote:
I have read that glyphosate is deactivated when it comes into contact
with the soil. Does that mean that you can spray weeds with
glyphosate one week and then safely plant shrubs in the same area of
land a few weeks later without there being any fears of the
glyphosate which was originally used?

Thanks,
Emrys Davies

Yes. In fact you could probably plant the next day. Glyphosate is only
effective when absorbed through the green parts of a plant. You could, I
understand, safely spray it on a deciduous plant which had no leaves.

--
Jeff
(cut "thetape" to reply)

Emrys Davies wrote:
I have read that glyphosate is deactivated when it comes into contact
with the soil. Does that mean that you can spray weeds with glyphosate
one week and then safely plant shrubs in the same area of land a few
weeks later without there being any fears of the glyphosate which was
originally used?

Pretty much. The limiting step is waiting for the sprayed weeds to die.
The weedkiller loses its activity on hitting the ground (as do one or
two others as they adsorb strongly onto clay and are then more slowly
chemically degraded).

Ivy seedlings and a few other extremely waxy plants can survive some
glyphosate spray, but it isn't something to rely on. And grass is
exquisitiely sensitive to it so be careful not ot walk across a lawn
after using the stuff if you got any on your boots.

Regards,
Martin Brown
** Posted from http://www.teranews.com **

Yes.

Be careful when spraying that it does not get onto your skin and that you do not breathe it in.

On 15 May, 18:57, "Emrys Davies" wrote:
I have read that glyphosate is deactivated when it comes into contact
with the soil. Does that mean that you can spray weeds with glyphosate
one week and then safely plant shrubs in the same area of land a few
weeks later without there being any fears of the glyphosate which was
originally used?

Thanks,
Emrys Davies

Actually this is a slightly dodgy claim. It actually depends on the
soil. The glyphosate isn't destroyed on contact with the soil, which
is often how it gets repeated but it gets attached onto clay
particles. If you don't have clay particles because your soil is
primarily peat or sand then it can't happen. Also this can't be as
instantaneous as the marketing speak seems to suggest. If it were it
would constitute a risk of fire or explosion. It will take a while

If your soil contains clay,as admittedly most soils do, then you are
probably OK a week later.

wrote:
On 15 May, 18:57, "Emrys Davies" wrote:
I have read that glyphosate is deactivated when it comes into contact
with the soil. Does that mean that you can spray weeds with glyphosate
one week and then safely plant shrubs in the same area of land a few
weeks later without there being any fears of the glyphosate which was
originally used?

Short answer is Yes.

Actually this is a slightly dodgy claim. It actually depends on the
soil. The glyphosate isn't destroyed on contact with the soil, which
is often how it gets repeated but it gets attached onto clay
particles. If you don't have clay particles because your soil is
primarily peat or sand then it can't happen.

For this to be a serious problem you have to be on wind sorted desert
sands or a perfect pure peat bog. Even a trace of fine clay will provide
enough surface area to lock it down. Extreme cold and darkness will slow
down the final decomposition too.

Also this can't be as
instantaneous as the marketing speak seems to suggest. If it were it
would constitute a risk of fire or explosion. It will take a while

"A while" for physical adsorption onto clay is a fraction of a second on
contact. It is the same sort of thing that makes activated charcoal take
out impurities in tapwater and on about that sort of timescale.

If you want to test it spray some glyphosate onto your soil, take a
sample of the newly sprayed soil and add mustard & cress seeds. If they
grow OK then you have your answer (may fail on peat based composts).

To test the limits you could try planting mustard and cress and using
glyphosate spray immediately for their first watering. I don't know if
they can survive that since it will leave active residue on the seeds
surface.

If your soil contains clay,as admittedly most soils do, then you are
probably OK a week later.

A trace of clay and the soil will lock up and deactivate the glyphosate.
The molecules persist for a while but they cannot do anything.

Regards,
Martin Brown
** Posted from http://www.teranews.com **

Martin Brown wrote:
wrote:
On 15 May, 18:57, "Emrys Davies" wrote:
I have read that glyphosate is deactivated when it comes into contact
with the soil. Does that mean that you can spray weeds with glyphosate
one week and then safely plant shrubs in the same area of land a few
weeks later without there being any fears of the glyphosate which was
originally used?

Short answer is Yes.

Actually this is a slightly dodgy claim. It actually depends on the
soil. The glyphosate isn't destroyed on contact with the soil, which
is often how it gets repeated but it gets attached onto clay
particles. If you don't have clay particles because your soil is
primarily peat or sand then it can't happen.

For this to be a serious problem you have to be on wind sorted desert
sands or a perfect pure peat bog. Even a trace of fine clay will provide
enough surface area to lock it down. Extreme cold and darkness will slow
down the final decomposition too.

Also this can't be as
instantaneous as the marketing speak seems to suggest. If it were it
would constitute a risk of fire or explosion. It will take a while

"A while" for physical adsorption onto clay is a fraction of a second on
contact. It is the same sort of thing that makes activated charcoal take
out impurities in tapwater and on about that sort of timescale.

If you want to test it spray some glyphosate onto your soil, take a
sample of the newly sprayed soil and add mustard & cress seeds. If they
grow OK then you have your answer (may fail on peat based composts).

To test the limits you could try planting mustard and cress and using
glyphosate spray immediately for their first watering. I don't know if
they can survive that since it will leave active residue on the seeds
surface.

If your soil contains clay,as admittedly most soils do, then you are
probably OK a week later.

A trace of clay and the soil will lock up and deactivate the glyphosate.
The molecules persist for a while but they cannot do anything.

Regards,
Martin Brown
** Posted from http://www.teranews.com **

So, do you reckon injection by syringe is an effective delivery method
for glyphosphates? I'm thinking particularly of borage where I could lop
off the top of the plant and inject into the main stem as I go. This
would presumably not deliver much volume of liquid but at least it would
be accurately placed. The roots are about a foot long so digging out
isn't really an option.

In article ,
stuart noble writes:
|
| So, do you reckon injection by syringe is an effective delivery method
| for glyphosphates? I'm thinking particularly of borage where I could lop
| off the top of the plant and inject into the main stem as I go. This
| would presumably not deliver much volume of liquid but at least it would
| be accurately placed. The roots are about a foot long so digging out
| isn't really an option.

You don't mean borage - that is an annual.

You probably mean comfrey or alkanet. In my experience, alkanet
doesn't regrow from from far below ground, so digging it out to
4-6" down is successful. Comfrey may be a bit harder, but I should
have thought that digging it out to 6-8" down would work.


Regards,
Nick Maclaren.

On 16/5/08 10:23, in article , "stuart
noble" wrote:

snip

So, do you reckon injection by syringe is an effective delivery method
for glyphosphates? I'm thinking particularly of borage where I could lop
off the top of the plant and inject into the main stem as I go. This
would presumably not deliver much volume of liquid but at least it would
be accurately placed. The roots are about a foot long so digging out
isn't really an option.

Borage! And there's me desperate for some. I'm the only person I know
that's killed it off! Don't get rid of it, just buy more Pimms. ;-))

--
Sacha
http://www.hillhousenursery.co.uk
South Devon
'We do not inherit the earth from our ancestors, we borrow it from our
children.'

stuart noble wrote:
Martin Brown wrote:

A trace of clay and the soil will lock up and deactivate the
glyphosate. The molecules persist for a while but they cannot do
anything.


So, do you reckon injection by syringe is an effective delivery method
for glyphosphates? I'm thinking particularly of borage where I could lop
off the top of the plant and inject into the main stem as I go. This
would presumably not deliver much volume of liquid but at least it would
be accurately placed. The roots are about a foot long so digging out
isn't really an option.

I wouldn't recommend messing about with syringes and injecting it into
plants. I think it has been tried for Japanese knotweed (hollow stems)
but is no longer recommended (which I take to mean it didn't work well
enough to be worth the effort).

Glyphosate is sufficiently lethal to green plants in growth that a spray
head adjusted to give a small jet can be accurately used. Failing that a
small paint brush. And if you hit something as collateral damage prune
the affected bit off immediately.

You seem to get a better translocation kill of bad weeds with extended
root systems if the weedkiller is slightly over diluted (by 10-20% which
makes it go further as well). For some reason buttercup seems to
tolerate it better than most plants.

Regards,
Martin Brown
** Posted from http://www.teranews.com **

Sacha wrote:
On 16/5/08 10:23, in article , "stuart
noble" wrote:

snip
So, do you reckon injection by syringe is an effective delivery method
for glyphosphates? I'm thinking particularly of borage where I could lop
off the top of the plant and inject into the main stem as I go. This
would presumably not deliver much volume of liquid but at least it would
be accurately placed. The roots are about a foot long so digging out
isn't really an option.

Borage! And there's me desperate for some. I'm the only person I know
that's killed it off! Don't get rid of it, just buy more Pimms. ;-))


Nick's right I think. It's not my garden, so I can't nip out and check,
but it looks like it's alkanet. The soil's good so it probably won't be
that difficult to get down to a fork depth, and hopefully I won't need a
weedkiller at all.
That just leaves the onion weed, which is occupying the shady side of
what should be the lawn. The grass stops where the weed starts, so I
guess it's preventing the grass from growing. Any advice on that front?

In article ,
stuart noble writes:
|
| That just leaves the onion weed, which is occupying the shady side of
| what should be the lawn. The grass stops where the weed starts, so I
| guess it's preventing the grass from growing. Any advice on that front?

Onion weed? I think that we need a bit more information :-)


Regards,
Nick Maclaren.

Nick Maclaren wrote:
In article ,
stuart noble writes:
|
| That just leaves the onion weed, which is occupying the shady side of
| what should be the lawn. The grass stops where the weed starts, so I
| guess it's preventing the grass from growing. Any advice on that front?

Onion weed? I think that we need a bit more information :-)


Regards,
Nick Maclaren.

Looks like a white bluebell and smells strongly when crushed. Allium
triquetum I think.
As I said, I'm working from memory here. Very frustrating :-)

On 16/5/08 12:06, in article , "stuart
noble" wrote:

Nick Maclaren wrote:
In article ,
stuart noble writes:
|
| That just leaves the onion weed, which is occupying the shady side of
| what should be the lawn. The grass stops where the weed starts, so I
| guess it's preventing the grass from growing. Any advice on that front?

Onion weed? I think that we need a bit more information :-)


Regards,
Nick Maclaren.

Looks like a white bluebell and smells strongly when crushed. Allium
triquetum I think.
As I said, I'm working from memory here. Very frustrating :-)

Aka Ransoms or wild garlic. Dig it up or spray it seems to be the only way.
I rather like it so when I had it in a previous garden, I always kept some
of it. But it absolutely fills the verges of some of the lanes round here.
--
Sacha
http://www.hillhousenursery.co.uk
South Devon
'We do not inherit the earth from our ancestors, we borrow it from our
children.'

Sacha wrote:
On 16/5/08 12:06, in article , "stuart
noble" wrote:

Nick Maclaren wrote:

Onion weed? I think that we need a bit more information :-)


Looks like a white bluebell and smells strongly when crushed. Allium
triquetum I think.
As I said, I'm working from memory here. Very frustrating :-)

Aka Ransoms or wild garlic. Dig it up or spray it seems to be the only way.
I rather like it so when I had it in a previous garden, I always kept some
of it. But it absolutely fills the verges of some of the lanes round here.

The local gamekeeper claimed eating a raw bulb of ransoms (wild garlic)
would cure the common cold. It certainly prevented infection as no-one
would go near him after he had eaten one!
(They smell very strongly of garlic when in flower, ie now)

I thought from the initial description it was one of the other wild
onion family plants that has huge numbers of bulblets and looks like a
cross between chives and onion. Almost grass or reed like in appearence.

Regards,
Martin Brown

** Posted from http://www.teranews.com **