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Old 23-05-2018, 08:26 AM posted to uk.rec.gardening
Martin Brown[_2_] Martin Brown[_2_] is offline
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First recorded activity by GardenBanter: Mar 2017
Posts: 267
Default Anthracnose on my vines!

On 22/05/2018 22:23, David Rance wrote:
In message , Jeff Layman
writes
On 22/05/18 08:42, David Rance wrote:
In message , Jeff Layman
writes

On 21/05/18 20:54, David Rance wrote:

In message , Jeff Layman
writes

On 21/05/18 16:41, David Rance wrote:
Can anyone tell me if Mancozeb or Captan are still available or have
they been banned by the EU?
Â*Â* For the first time I seem to have a bad infection of
anthracnose on
my
vines. Advice on treatment seems contradictory. Some say that
sulphur
treatments work, others say they don't! Today I've sprayed with
Bordeaux
Mixture but I'm not convinced of its efficacy.
Â*Â* David

Neither mancozeb nor captan are approved for home use.

Â* But I always used Dithane which is 70% Mancozeb (according to the
empty
packet I have here).

Bordeaux Mixture is also not approved (was it an old container you
use?),

Â* Bordeaux Mixture is still readily available here in France.

I forgot that you were in France. Of course, the French have always
interpreted EU law to suit themselves. I think you will find that
Bordeaux Mixture is not approved in the EU for *amateur* use. But it
still may be for professional growers, and I understand that there are
a few of those growing vines in France.
Â*Yes, it has been banned but there was such an uproar from vine growers
that the last I heard was that they were going to rethink the ban. I
wouldn't be surprised if the same weren't true in Germany. I can well
remember staying in a wine area on the Mosel some years ago where they
had alerts for when mildews were about to strike and a light plane would
go back and forth along the banks of the river spraying Bordeaux
Mixture. Having suffered peronospora (downy mildew) myself on my tiny,
tiny vineyard I can testify to its destructive power where, if not
treated, one loses the whole crop.
Â*I'm in Normandy which is not a wine growing area and so it was several
years before peronospora struck here. But if I were living in a wine
growing area I could be prosecuted for *not* spraying.

When you say "readily available", do you mean that in the sense of what
we would call a garden centre (or maybe supermarket) here, or is it an
agricultural merchant selling in larger quantities?
Â*Both!
Â*However, I'm now stuck with another disease which threatens my whole
crop and I have nothing left with which to fight it. Can you suggest a
substitute?
Â*In case I've misdiagnosed, here is a photo of an affected leaf:
Â*http://www.rance.org.uk/chameau/anthracnose.jpg


It does look like it, unfortunately.

I spent some time looking up the situation regarding Bordeaux Mixture
in the EU, and it is confusing to say the least! I came across this
newspaper article which goes some way to explaining the confusion:
https://www.irishexaminer.com/breaki...entury-pestici
de-survives-for-another-year-827084.html

The last few paragraphs sum up an EU "fudge" which seems only too
common with regard to chemical treatments. Mind you, I am a bit
surprised to see that of the two member states which voted against
reapproval, one of them was France!


Interesting article. I'd heard that they were getting around the ban but
didn't know the details. Can't understand France not voting for
reapproval. I wonder what their reasons were. After all their wine
exports will suffer if they can't control blight on their vines.


Isn't there a problem with build up of copper in the soils and
groundwater around vineyards due to overuse of the treatment.

If you search at that link I gave you for fungicides (dropdown in
bottom box) you will find quite a few hits, but unfortunately they are
all for use on ornamental plants, not those with an edible crop (other
than the Bayer copper oxychloride product). Of course, what you do
with the product once you have it is another thing entirely.


Of course! ;-)Â*Â* I have to return to the UK tomorrow so I have a month
now to do some research before my next visit.


Simplest way out is research the ingredients for the classic copper
based fungicides and buy the ingredients on Amazon or eBay. Amazing what
you can get online these days even if the suggestions for what else to
buy are somewhat disturbing. I bought some fairly strong peroxide to
bleach something recently and it suggested acetone to go with it!

--
Regards,
Martin Brown