On Sat, 23 Jun 2007 15:51:32 CST, Galen Hekhuis <>
wrote:
>I have three ponds also. The front one and the back one are covered
>in duckweed, but the middle pond (near the house) doesn't have a bit.
>I know it has been "inoculated," I've seen ducks, cormorants, ibises,
>egrets, and others visit the pond. I've even seen duckweed floating
>in the pond, but I guess it just dies out because the pond stays free
>of it.
>
>I've been a cave explorer for some 40+ years and now live in some of
>the best cave diving country in the world (northern Florida). Having
>spent so much time underground and having friends that actually swim
>around in the underground water I am extremely anal about putting any
>kind of chemical where it can get in the ground or groundwater.
>Herbicides are right out for me. I have no fish in the pond, either.
>I haven't the foggiest why I don't have any duckweed there.
>
>I've tried to search for solutions but haven't found hardly anything
>promising. Methods of biological control (mainly fish that eat
>duckweed) have mixed reviews, the majority seem to think it a pretty
>iffy proposition, if not an outright poor method of control.
>Mechanical methods (skimming and the like) seem to provide only very
>temporary fixes. That leaves chemical methods (herbicides), and aside
>from my reluctance to go that route it isn't a cheap way to go,
>either. Besides, just about anything that kills duckweed kills a lot
>of other stuff too, there doesn't seem to be anything like a duckweed
>specific herbicide.
Maybe it is just my fish. But my little inside pond was covered with it
after over wintering the tropicals. I was thinking what a job it was going
to be to net it out so I could clean the muck on the pond. Then I purchased
4 small wakins. The only duckweed in there now is what washed up on two
fake lilies where the fish can't get to it. I was able to vac the bottom
out a few days ago. :-)
My Q-tank is another place it disappears with relish. Probably because
there isn't much else to eat, other than the food I throw in. IMHO, if the
fish aren't fed, they'll eat the duckweed. But in a natural pond, there is
a whole lot of other things to eat.... YMMV. ~ jan
------------
Zone 7a, SE Washington State
Ponds:
www.jjspond.us