Duckweed Control

My Father-in-Law (FIL going forward) has a pond that has a bit of a duckweed problem. He has the following fish: Grass carp, catfish, bass, blue gill, red ear hybrid, and crappie. The duckweed is getting out of control and he is about to use some GICK (sp) on the pond to get rid of the duck weed.

Using the duckweed as compost is not an option for him.

Perhaps he has a Duck shortage? I'm under the impression they love the stuff and will gobble it up at any opportunity.

Lina Ackerman wrote:Perhaps he has a Duck shortage? I'm under the impression they love the stuff and will gobble it up at any opportunity.

He had ducks at one time but my MIL got tired of the poop all over the porch.

Ahhh What you need is a duck AND and fence. That ought to do it.

Depending on how much of it there is, you could also skim it yourself and dry it in the sun on the lawn. Or lay it on the lawn just before mowing. It should mulch up just fine.

Craig Dobbelyu wrote:Ahhh What you need is a duck AND and fence. That ought to do it.

Depending on how much of it there is, you could also skim it yourself and dry it in the sun on the lawn. Or lay it on the lawn just before mowing. It should mulch up just fine.

The fence isn't an option unfortunately, its a ravine that was made into a pond (steep sides that make it PITA to fence) and he gave water access rights to the person living on the other side (neighbor may not want fence on his property). Like I said in the op, composting isn't an option, both the FIL and the FIL's neighbor don't have the time.

Does he need more grass carp or something?

hi E Little,

excessive duckweed is a sign of high "nutrients" in the pond
this may be from the fish or maybe from runoff from fields
if the pond is built from a ravine, there may not be enough shoreline vegetation to remove nutrients and balance the system
so the pond may act more like a tank than a pond and may need flushed occasionally if possible

removing of duckweed will help get rid of nutrients (spread them on the garden and flower beds as mulch)
perhaps a floating island of plants could be used to remove the nutrients
but you should check for sources of nutrients
poisoning the duckweed may just cause an algae problem as the nutrients remain in the pond

My FIL did say that he has a leaf problem from the trees around his pond, when he built it they weren't there but over the last 15 years there are quite a few trees and almost all their leaves land in the pond. This could be the nutrient source that you are referring to. I will mention the floating island of plants and raking off the duckweed onto his garden or something. Thanks!

After years of not having problems with duckweed on our half-acre pond it suddenly came up and covered it entirely this year... We could not even see the water because the covering was so complete. Our geese wouldn't even go into the pond.. After various attempts at trying to rake it off we finally settled on making a thin 20 foot long floating contraption that we pulled back and forth over the pond which would "rake" the duckweed to one end of the pond where we have a drain that the duckweed would get sucked out through... It has taken us many hours of work to do it but we finally have the pond looking beautiful again... (and we are going to be careful to not let it establish i1self again... The floating contraption consists of a 20 foot length of PVC pipe capped on both ends which is then nestled into a very light weight piece of metal that serves to catch the duckweed and pull it along... The PVC pipe by itself isn't effective as the duckweed flows under and around it..... The contraction is pulled from both ends so that it pulls the duckweed towards the drain ... When it is pulled back to the other end of the pond we just pull it from one end so that it goes back right through the duckweed... It uses a lot of rope to do this and I found that Harbor Freight sells 600' of a floating 1/4 rope that worked perfectly for the job...

ah duckweed

Hi David,

welcome to permies

In permaculture we try to find uses for "excesses"
duckweed is nature's solution for the excess nutrients in your pond
removing the duckweed, however troublesome, will help remove nutrients
duckweed can be a valuable product as a animal feed or mulch
so instead of considering it a problem, think of some places where it can be used on your property

here some info
http://www.mobot.org/jwcross/duckweed/duckweed-charms.htm
http://www.mobot.org/jwcross/duckweed/weed_control.htm

David, could you post a picture of your duckweed catching device. I'm not clear on how you did the metal thing.

I don't have duckweed but I could use it for animal feed and compost. There are duckweed ponds within a mile of my farm and I have an electric winch that can pull things onto my trailer. I'm trying to figure out how to load a few thousand pounds of duckweed in an efficient manner.

You need some Tilapia in that pond. Tilapia love duckweed grow super fast and taste great.