Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants I have a weed & algae problem

Ok, I knew it was coming, I have shallow 4:1 slopes, and now I'm having major cattail issues & algae problems.

Weeds-1
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Pic's from 1 month ago

What I don't get is, the ponds are connected via a 12" culvert pipe, the large pond has a ton of weeds, and green stringy algae under the surface, and a lot of floating green/brown bubbling algae, and cattails, the small pond has virtually nothing. Not sure why they are so different.

The large pond seems to accumulate a heck of a lot of decaying plant matter, the small pond none.

What is the solution here?

I can't imagine a windmill aeration system alone is going to be a panacea?

If I do start to aerate, how long will it take? Before I buy a windmill, I wanted to try a couple bottom diffusers (12ft deep) and a small diesel engine with an air pump. I have no power near these ponds.

If I run the aeration for a week or two, is that going to make a difference?

That's a mess and has happened in a hurry. More than likely, some seeds blew in from another pond and got the cattails started.

Go to the Aquaplant website posted by TAMU. You'll find the right chemicals to take care of both problems. I get my chemicals from Tractor Supply Company but they seldom keep surfactants.

If the cattails develop a rhizome at the top, that's the seed head. Cut it off before it has a chance to mature.

I'll let someone else comment on aeration.

I'm not as concerned about the cattails as I am about the algae.

It took me one weekend to pull the cattails and leave some bunches of them, where I wanted them. I do want some, so if I have to do that once in a while, no big deal.

It seems like the dying cattails from last year, plus poplar & maple leaves from last fall make up the majority of the decaying plant matter in the pond.

My concern is, we've only had a few warm days. I can't imagine what the algae problem will be like all summer long.

I am afraid to dig out the shallow 4:1 slope, as it will ruin my clay lining.

The decaying plant matter on the shallow banks all the way around the pond is making for a large surface area for algae manufacture.

I need to find a way to get this under control without digging out the banks, and risk creating a leak. The soil under the 1 ft thick clay lining is sandy loam, it will leak for sure.

Looks to me like you have a very fertile pond like mine. Short term spraying with cutrine will kill the algae. Only do half the pond at a time and wait a few weeks to do the other half. This will prevent an oxygen crash and fish kill. Long term solution is reducing the nutrient load and adding aeration to increase your natural bacteria's ability to break down the organics. Weeds can be targeted with specific herbicides.

Well, I have been raking out the algae the last couple of weeks, then we had a few nights of hard rain.

Algae Gone

Most of the algae on the bottom is gone too, so, not sure what's going on...

Did the algae come back yet? In our pond the rain just beats the algae into the top of the water column. After a few days to a week, the algae reorganized and forms on the surface again. Hopefully this is not your case, but be prepared.

We use Crystal Plex sprayed with a tank sprayer and had really good results killing the algae on our lake. It has copper sulfate in it that really zaps the stuff.

It has only been 2 days since the rain, it's going to be a hot & dry week, so I'll see what happens...

I like the fact you are not using a lot of chemicals to remove the algae and cattails. Plus removing them from the pond and dumping them on shore is prudent to prevent internal loading.


Both are coming back though. Cattails have pretty nasty rhizomes, you can cut th etop multiple times, and they will keep reemerging. I have 3-4 cuts on some ponds I'm working. Good news is, you keep cutting, especially down to the water's surface, you will deplete the rhizome. I call it my 3S methods. Submerge, Suffocate and Starvation. I think yours cannot be as well established as mine, over a decade old. Also, your must have come in from the wind or water surface, from the brown seed tops or catkins. I would imagine you have some in the vicinity. Unless you have always had cattails?

The algae is really not that bad. Sometimes it actually goes away with warmer temps and certain other pond events that compete with it. Can't hurt to get it out also. I might consider tinting or introducing some beneficial bacteria to start reducing new growth. Both don't try both. That is a either or. Aeration helps, as well as algae eating organisms. Kudos for attacking the stuff early and being proactive. Imagine letting the stuff go unchecked for over 10 years, that is the usual time a customer calls me.

I didn't actually cut the cattails, I have been pulling them out from a boat, or with my waders.

I figured that was better than just cutting. Sometimes the entire root system comes out, but mostly, just the white part of the root comes out.

These ponds are only 3 years old, and for the large one, this was the first spring it was full. The ring of cattails I have been pulling is actually where the waterline was last year.

I believe the main contributor to the FA problem in the large pond is, the water is 3ft higher than last year, so what was on the shallow banks in terms of weeds & grass, is now under water, rotting away...

I have not used any chemicals yet.

I see, that makes a bit more sense. Boy, pulling the cattails up vertically is tough. That is the strength of the plant. Side cutting just below the surface to right above the rhizome is pretty easy with the right tool. Old dead growth is the hard part, and you are on top of that. I would imagine you have and upwind source of seeds blowing in. If that is the case you may have a neverending battle for control of the shoreline new growth. You might have luck spraying a preemergent on the shoreline at low water also.

If you are establishing a new high water mark and are submerging old terrestial growth, that is an algae maker for sure. But it looks to be you are doing everything I would do, early eradication, no chemicals, removal of material. After this algae bloom you might want to sit back and see if that depleted some of the nutrients. Also with a new pond I would probably introduce some beneficial bacteria. Get in front of the nutrients and muck/sludge. I would avoid chemicals and stay the course if the labor does not bother you. The keys are early removal and staying on top of it. Good job.

The FA has not come back in the big pond. Oddly enough, it appears to be the small ponds turn with the FA, but only minor amounts along the shoreline that I have been easily raking out the past week.

I did nothing chemically. Much of the dying plant matter along the shorelines seems to be gone.

I guess This may have been a case of new ponds which have only been full since last fall going through some growing pains?

I finally got a windmill, hopefully it will be up and running soon if the weather cooperates.

ETD Don't expect the windmill to fix your algae problems. In fact you may not see much of a difference in less algae growth due to using a windmill. Aeration helps to reduce algae primarily in ponds where the nutrients are coming from decompostion in deep water anaerobic (no oxygen) conditions. Often filamentous or sting algae is being 'fed' by nutrient runoff and aeration does not do a lot to reduce fertilizer/nutrients dissolved in the runoff / watershed water. Just for my being nosey, please keep us 'posted' on how well the windmill does at reducing your algae. Windmills are okay and much better for a pond than no aeration.

I think one of your major stimulants for the algae besides the runoff nutrients is the shallow slopes (4:1) and amount of shallow water that you have. both are very condusive to allowing filamentous algae (FA) growth. I also noticed in your pictures that your water is clear. Clear water allows sunlight to penetrate to the bottom in deeper areas thus allowing FA to become established in more bottom areas and overall more algae.

Stay on top of those cattails. Always pull out new growths. If you want a similar plant along the shore use water iris - shorter, do not spread as fast, do not grow as deep - much better shoreline plant IMO.

This spring, we've had so much rain, the water has stayed brown, along with the water level 1.5ft higher than last spring. No real algae to speak of at the moment.

I do have serious deep water anaerobic issues. I found that out when I tried an airpump + diffuser stone last year, the gasses coming from the bottom smelled horrid. And the O2 level down there was only 2ppm, as opposed to 11ppm at the surface. That is primarily why I decided to spend the money on the windmill. When I pulled out the diffuser stone this spring, it was covered in rotten black nastiness I sure hope the windmill helps with that.

The algae, I'll just have to keep raking it out whenever it shows up...

Some pictures of the windmill erection: Outdoor Water Solutions

Maybe you could solve your problems by using silver carp and grass carp?
Grass carp could eat cattails but silver carp would be a fighter against algae.

I stocked grass carp last year.

However, I decided not to stock any other fish until I get some aeration.

Another problem I have is the windmill location. I carved my pond area out of a 80 year old forest, so the area is surounded by 80-100 ft tall trees. Layout

There are buildings & electrical service shown on that layout, but they don't exist yet That's why I went with a windmill for now, instead of an electric setup. I'm hoping the windmill works enough days of the year to get me some aeration.

I really need to improve water quality before I add more fish.

That fathead, shiners & grass carp are doing ok, but I'm not sure how well the SMB, YP, PS & WE will enjoy the current water quality.