North American Fruit Explorers mailing list at ibiblio

[Road's End Farm <organic87@frontiernet.net>]

On Mar 25, 2008, at 4:56 PM, GHG3@aol.com wrote:

> <x-tad-smaller>Interesting that this topic on fireblight and use of the bordeaux mix has come up this week, since I've got a post scheduled for Friday morning regarding this topic, on The Heirloom Orchardist.  The Bordeaux mix came about in the mid 19th century-ish....could anyone tell me if it is acceptable today in an organic growing program?</x-tad-smaller>
> <x-tad-smaller> </x-tad-smaller>
> <x-tad-smaller>George</x-tad-smaller>
>

Bordeaux mix (defined as "the precipitate of the reaction product of copper sulfate and calcium hydroxide") is on the restricted list according to my copy of the OMRI Generic Materials List.

What that means is that it will probably be allowed by the certifying agency, if the certifier is convinced that you have a good reason to use it, and if you're using it in a fashion that, to quote the OMRI list again, "minimizes copper accumulation in the soil". (An input can be categorized as "allowed", "restricted", or "prohibited". Restricted-use items are allowed under some conditions but not others; the conditions will vary with the item.)

Anyone contemplating certification, or already certified, should check with the certifier before use. 

--Rivka
Finger Lakes NY; zone 5 mostly