Hyacinth spraying on Vaal

[Gael]

I have been informed by Dirk (barbus13) that they will be spraying herbicide on the water hyacinth from Schoemansdrift all the way to Bloemhof dam starting today.

I am told that it safe to fish during and after the spraying operations

[Wade]

Nice to hear that they are doing something.

We spent some time over the weekend near Bothaville and the hyacinth was a nightmare. Occasionaly a piece so large would knock you off your feet, literaly....

[Korrie]

at one stage they where looking at importing a beetle that eats the hyacinth, does anyone know if that happened?
Ifso, how succesfull or not succesfull was the little critters?
Maybe not too succesfull if they have to spray the hyacinth?

[MaXiMuM]

they did, but our cold winters killed them off. So if they want more beatles they need to breed them and let them out on the water in spring...

This cannot be sustainable.

Mike

[Scythe]

Which then brings the whole genetics debate into question again in the sense of would it be ecological suicide to alter the beetle to be more resistent to cold and in so doing risk the possibility of other aspects of the beetle being changed with the result that you have a new environmentally hardy invader present buggering up some other part of the eco system.

[Wade]

It is like a well balanced enclosed ecosystem, once you start messing with it you cant stop

[Fingers]

I like the fact that the beatles die off every winter. At least this way they are not going to get out of hand and even if you have to spend money every year breeding new ones - is it not better to spend money every year on a "natural" control method than on a chemical one?

[Scythe]

... is it not better to spend money every year on a "natural" control method than on a chemical one?

For sure, but who is going to foot the bill when there is little or no action being taken on increasing waste water capacity ? At this rate in 5-10yrs the hiacynth will be the only thing growing in the Vaal.

[Korrie]

For sure, but who is going to foot the bill when there is little or no action being taken on increasing waste water capacity ? At this rate in 5-10yrs the hiacynth will be the only thing growing in the Vaal.

I heard, not so sure, maybe the more informed members can help me.
The hyacinth are actually a blessing in disguise.
They take a lot of the "crap", chemicals and polution out of the system.
The hyacinth uses this as "fertilizer"
Do any of you know how much they take out, absorb?
What effect does the rotting hyacinths have on the oxygen levels in the water.
Previously a lot of the fish deaths was blamed on the partial decomposing material that was on bottom of the river. When the sediment got churned up, the rotting process was activated. WHich used up the available oxygen in the water. How much of the muck on the river bed was from half decomposed hyacinths?
Comes down to A. does the hyacinth improve the quality of the water by absorbing all lot of the muck in the water?
B. does the decomposing hyacinths in the long run have detrimental effects on the river by creating anearobic conditions?

[Korrie]

I heard, not so sure, maybe the more informed members can help me.
The hyacinth are actually a blessing in disguise.
They take a lot of the "crap", chemicals and polution out of the system.
The hyacinth uses this as "fertilizer"
Do any of you know how much they take out, absorb?
What effect does the rotting hyacinths have on the oxygen levels in the water.
Previously a lot of the fish deaths was blamed on the partial decomposing material that was on bottom of the river. When the sediment got churned up, the rotting process was activated. WHich used up the available oxygen in the water. How much of the muck on the river bed was from half decomposed hyacinths?
Comes down to A. does the hyacinth improve the quality of the water by absorbing all lot of the muck in the water?
B. does the decomposing hyacinths in the long run have detrimental effects on the river by creating anearobic conditions?

C. what will the Vaal river's water quality be without the hyacinths