Canadian pond weed

[Guest davidP]

Tim Kelly Posted :

Has anyone got experience of stocking grass carp over here? If we put triploided fish in and something went wrong at least they wouldn't be there for ever......

 

 

I doubt there's such a thing as a triploided grass carp because they cannot breed in British waters. They are somewhat unusual in that they lay their eggs directly into the river flow and the eggs are washed downstream until they hatch at which point the fry seek cover. There are quite simply no rivers in the UK long enough (or probably warm enough) for this cycle to be completed. There are only a few rivers in the far east where they breed successfully although I think I read on a site somewhere that there was some evidence of them managing to breed in the Mississippi.

 

 

[This message has been edited by davidP (edited 24 January 2001).]

[Guest Newt]

Originally posted by Bruno Broughton:

Grass carp - you need a lot, they are expensive and they won't eat anything much until the water gets to 15C (and won't really chomp until it's 20C). Cost? You're probably looking at £500-£700+ per acre!

 

Bruno - you are the expert and I am not trying to argue - just to get information. The usual rule-of-thumb here for grass carp is 10/surface acre for moderate weeds and 20/surface acre for really heavy weed. To run in the cost area you cite of £500-£700+ per acre, either these fish cost a lot more there than in the US or you see a need for a much higher population.

[Guest Steve Burke]

Bruno advised me at Wingham, and thanks to his help we now our canadian pondweed problem under control. And, believe me it was a problem! We had 15 feet of canadian pond weed in 15 feet of water. It covered nearly all of both the lakes, and by late summer was impossible to fish through.

 

As already mentioned in this thread, you can overdo matters. Because of this, and because I'm restricted due to Wingham being a nature reserve, Bruno recommended we try a liquid called Reglone at one quarter of the manufacturer's recommended strength. (I get the impression that manufacturers always recommend a higher dosage than is needed - you buy more that way!).

 

This was in 1999, and unfortunately it had little effect. I'd hasten to add that this wasn't Bruno's fault as I was restricted in what chemicals and what dosage I could use, and had been told to err on the side of caution.

 

Last year we had permission from the nature conservation people to use anything we like. I then got the additional permission everyone requires from the Environment Agency, which needed a site visit. This took some time, but early last spring we applied Casaron G at full strength, again on Bruno's recommendation. We also followed his advice and treated only 5 acres of each lake, one of which is 15 acres, the other 40. BTW, Casaron should be applied before the weed gets going, whilst Reglone can be applied until high water temperatures make weedkilling dangerous due to lack of dissolved oxygen when the weed rots.

 

On the smaller water, our carp only lake, 95% of the canadian pondweed has disappeared over the whole of the lake. Due to the nutrients in the weed being recycled we've also had the growth spurt that Bruno predicted.

 

On the 40 acre Coarse Lake, the 5 acres of margins that we treated have almost no canadian pondweed. It's also disappeared on over half the rest of the lake as well, although "friendly" weed such as various varieties of potamogeton have thankfully been unaffected.

 

It's just possible that the canadian pondweed, which goes in cycles, may have died off anyway, espially if it had been weakened by the weedkiller. However, one way or another, Casaron G has been a tremendous success at Wingham. Reglone at full strength may also have worked as well, but, unlike Casaron, you need to use more in deep water. As the lakes at Wingham are deep, Casaron works out less expensive for me than Reglone. Casaron GSR, which is the same but more concentrated, would have been cheaper still, but as Bruno pointed out has now been discontinued.

 

BTW, whilst raking many weeds can be effective if you've enough manpower, it's no good for canadian pondweed. This is because each tiny bit cut off starts a new plant. In fact all you'd be doing is making the problem worse!

 

Finally, Bruno's practice notes are very detailed and are invaluable. Even better, get Bruno to come along and give you a full survey. It's not that expensive and in fact is almost bound to pay for itself. It's certainly been the best money I've spend on Wingham!

 

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Wingham Fisheries

http://www.anglersnet.co.uk/fisheries/wingham.htm

[Guest Keith Truscott]

Hi Eelfisher,

 

Very sorry to hear the news about Tim, he was a true gentlemen who loved everything to do with fishing and was a pioneer amongst the beauracy of the old water boards with his ideas on how waters should be managed. I always thought it was a loss to fishing especially in the Anglian Region, when through frustration he left to go to Scotland to add his knowledge to the preservence of the salmon, I am both pleased and proud to have known him and can think of no better tribute than you and your fellow anglers have done.

 

With regard to the Canadian pond weed topic I think Bruno with his knowledge and experience has summed this up very well and Steve's experience at Wingham which I hope to fish one day only proves the point.

 

No matter how small your Club or Syndicate is or the limited finance you have available it pays in the long run to get an expert in to advise you what to do with whatever problem you have with your water, it's the cheapest and most successful solution in the end.

 

I'll collect my commission anualy Bruno.

 

Keith