Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Mealweed covering our pond

Hi everybody - Here in Yankee Virginia we have a one-acre pond that has a 65 acre watershed. Geese have become native over the last 12 years and we believe they have brought in a floating plant known hereabouts as "mealweed" because of its feel when you pick up a sample between your fingers. From June through late September it covers the pond totally. Chemical algicides haven't been effective and we don't want to harm the fish we have stocked. A couple years ago we tried skimming with a 50-foot homemade boom, but a week later the scum grew to cover the entire surface. I've been pumping in air 24/7 during hot weather. We should dredge to four foot depth but our 16 homeowner members are loath to cough up the funds. Are there skimming booms we could buy reasonably?

Welcome to PB.

Can you id the weed ? Sounds like you are describing watermeal or duckweed. See this:

http://aquaplant.tamu.edu/database/floating_plants/watermeal.htm

http://aquaplant.tamu.edu/database/floating_plants/common_duckweed.htm

I second the welcome, Dick! Glad you found Pond Boss. I agree with ewest that you may well have either duckweed or watermeal. I've got a watermeal problem and know what you mean when you mention the feel of it. Reminds me of cornmeal, just not as versatile or desirable!

Skimming is certainly a good non-chemical solution, but it's not going to eliminate the problem absent a massive amount of continuous effort, I suspect. You might eventually get it under control that way, but that's going to be a LOT of work. By the way, if it is, in fact, watermeal or duckweed, chemical algicides will not kill it as it's not algae. There are other chemical solutions, but those can be pretty drastic vegetation killers and can lead to other issues if not administered very carefully.

Thanks for the replies! Our Lake Committee has decided we have watermeal. Now we're considering that skimmer and/or corralling the stuff with a boom between a couple of electric-powered boats and/or a VERY large fan to push the layer of weed across the pond toward our outflow pipe, which is 18 inch diameter PVC.
Main problem is of course eutrophication from overuse of fertilizer by folks around the watershed who must have lush green lawns, together with lots of eroded silt that periodically fills the silt trap and then the pond itself during heavy rains. The erosion began 15 years ago when our County built a dry well to handle stormwater; its outflow has now dug a six-foot ditch where there had been a thin natural trickle feeding the pond. All that dirt is now filling our pond. The ditch is maybe 500 feet long. County shrugs its figurative shoulders.

I always welcome someone new who rants about green lawns and apothetic government agencies. I think your fix on the watermeal should be sufficient. But I also agree on your assessment of why it is there, that fertilizer runoff is just brutal to a pond's ecosystem. You can never get those excessive nutrients out or from continually reloading because of people having to have a greener lawn than the neighbor's. And yes, those natural trickle streams were made over decades. You start breaking up that top layer and exposing soft soil and soon that ends up where you don't want it with even more problems. What a bummer. Does not sound like you have the room but if all that stuff is puring in I like to have a frontage or inlet bog. A sediment and nutrient trap. I'm making one for a pond I'm working on now and don't even have those issues. In many naturally occuring ponds there are wetlands or bogs draining into a pond. It helps create a seperate ecpsystem that works in tandem with your pond, like a symbiotic relationship. Good luck to you, you seem to at least have a plan.

Welcome to the forum Dick... Fairfax County definitely has a serious problem with golf course geese pooping and taking over everywhere! Oakton is a very nice area. What types of fish do you have in your pond?

We have stocked with bass years ago; there are plenty of bluegills, and last year we put in a dozen Israeli Carp because the original dozen had died of old age. Then there are the snappers . . . no one swims any more. All these changes in the last 15 years. All change is not progress.

I think I would talk to the county and say fix our pond you impacted and fix your mess.

I agree with PF on the sink/trap. I must have missed the watermeal fix. Skimming while helpful will not get rid of the problem even short term (3 mths). You have to break its reproductive cycle or seeds will keep floating up.

Dick, I had a 3/4 acre pond completely covered with Watermeal. One treatment with a fluridone based chemical (I used Whitecap) and the pond has been Watermeal free for 2 years.

Again, not solving the root of the problem (nutrient levels) but a worthwhile temporary fix in my opinion.

I ruled out the fluridone when he said HOA were loathe to spending money or funds. There is no inexpensive fluridone. There is expensive, and more expensive.

Got the message! Another idea floated here: Be a whistleblower and report the situation to the EPA as damage to a sacred wetland, all caused by the evil county not handling dry pond outflow correctly. The idea being to get two groups of beancounters fighting with each other. Hereabouts, however, the spectacle of intergovernment disagreement is all too common to be funny any more, plus we all know how expensive for all taxpayers it can become.