OT-Duckweed

[Fishbonker]

I know this is off topic, but a co-worker just asked me about treating weeds in his pond. He thinks he has Duckweed and wants to know how to kill it. He describes it as small round individual green plants. He heard that copper will kill it and needs to know if that is indeed true and how to go about finding copper.

Any help?

I figured all of my other pesticide questions have been answered in this forum so I thought I'd try this one.

Thanks.

The 'Bonker

 

[muddy]

Copper sulfate is what will usually control pond scum/algae problems. As far as your buddy throwing it in his pond, I suggest NOT doing it. I am pretty certain that you need a pesticide applicators license to treat in the amount that he's probably going to have to. Here's a link to the Iowa Department of Agriculture and Land Stewardship pesticide bureau. Poke around there or call the chief of the department Chuck Eckerman, his number is on the top of the page. One simple phone call could save ya a big fine.

Good luck.

 

[Fishbonker]

Thanks Muddy.

I do hold a private applicators license, but I only got it to buy Tordon 22K.

The 'Bonker

Edit: I followed that link and came up with two copper sulfate based pesticides that are nonresticted use. Fixed him right up with the info. I strongly encouraged him to call the Extension office too.

The 'Bonker

 

[HighJumper]

If you have duckweed you will need diquat or fluridone to do in water treatment that will not harm the fish. Another option is to go low budget nuclear and use 2,4-d which will kill fish if you get concentration too high. Supposed to treat in early spring when the plants start to show up again. Good luck. You may want to run a steak through the heart of the duckweed just to make sure.

 

[Fishbonker]

Thanks, I'll pass that along.

The 'Bonker