Subject: HELP: ERADICATION OF AZOLLA

From: [email-masked]
Date: Thu, 30 Mar 95 13:54:10 +1200

I am making this enquiry for a friend who is farming in a dry region of 
South Africa. His dam is overgrown with Azolla to the extent that the
entire water surface has been covered. Does anyone have any experience 
with eradicating this water fern?

Any help would be much appreciated

Christine Voisey
email: [email-masked]

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From: [email-masked] (mel turner)
Date: Thu, 30 Mar 1995 11:52:04

>Any help would be much appreciated

If it is really Azolla and not Salvinia (better known as a serious  aquatic 
pest), the farmer may actually benefit from allowing it to grow, periodically 
skimming off the excess and using it as "green manure"--- Azolla has a 
symbiotic relationship with nitrogen-fixing cyanobacteria (Anabaena azollae) 
and thus can be used to enrich soil.
mdt

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From: [email-masked]
Date: Mon, 3 Apr 95 12:37:17 +1200

In Article <[email-masked]>
[email-masked] (mel turner) writes:
>In article <[email-masked]> [email-masked] writes:
>>[email-masked] (mel turner) writes:
>>> [email-masked] writes:
>     As someone else posted,  Salvinia would be using the excess (farm 
>runoff?) nutrients from the pond water, whereas Azolla would in addition be 
>able to fix atmospheric nitrogen.   Someone with say, a rowboat, a long &  
>fairly fine-mesh net, and assitants on shore should be able to skim large 
>areas of pond surface fairly quickly, and the effect would be to remove large 
>amounts of excess nutrients from the water that could then be returned to the 
>soil.
>mdt

Thanks for your suggestions everyone. I spoke to a scientist who said the
only way to control it effectively using chemicals was to spray with paraquat.
He said if the dam was deep enough the fish would not suffer toxic effects. I
feel the best option to avoid damaging the dam is to harvest it. I will send
the farmer your thoughts and let you know what eventually happens.
Christine.

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From: [email-masked] (MR J GERBER)
Date: Sat, 1 Apr 1995 09:59:14 GMT

In article <[email-masked]> [email-masked] writes:
>From: [email-masked]
>Subject: HELP: ERADICATION OF AZOLLA
>Date: Thu, 30 Mar 95 13:54:10 +1200

>email: [email-masked]
                                                                             
Christine:                                                          
The only way to get rid of that shit is to clear it manualy. 
Herbicides do work, but that renders the water useless for both 
livestock and irrigation