Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Trying to save pond from total coontail takeover

I’m looking for some confirmation that my thinking is correct and that what I am proposing to do is reasonable. We bought the property we live on now in Jun 2002. Part of the property is a 2.5 acre pond that is shallow on the north half, pretty much 3 feet deep in two coves, and then sloping down to the deepest part by the dam, which is about 12 feet. It was created in the very early 80’s, and it appears to have about a foot and a half of muck in the bottom

In 2004 we noticed that we were having pretty big FA blooms that weren’t going away so well. I contacted Vertex water systems and we bought a system with a 3/4HP compressor and 3 dual disk air stations. We’d always had a problem with water primrose, but we were able to use a herbicide on it to get rid of it.

In 2006 we had a real bad FA bloom that wasn’t going away, and we ended up contacting Clean-Flo. They proposed a second aeration system, also a 3/4 hp compressor, one 12in diffuser and 2 6in diffusers as well as some enzymes and beneficial bacteria. We continued to get FA blooms, and water primrose. We were still keeping the water primrose under control, but the FA hung around longer in more parts of the ponds. We continued to put in more beneficial every year, including this year, but the muck layer persists.

Since 2010 we have been having a plant boom of coontail covered by duckweed and watermeal and interspersed will FA blooms and some really nasty smells. 2010 was the first year we couldn’t take our boat to all areas of the pond because we’d get the prop fouled in massive amounts of coontail, so way started manually gathering the coontail/duckweed/FA. We worked as well as we could going out in the boat and between my wife and I we get 10 5-gallon buckets full of the plant mixture by reaching over the side of the boat and pulling it in. It is very time consuming because we end up dumping the buckets in the font end loader on my tractor to haul it out of the watershed while my wife pumped the water out of the boat for the next run. I don’t know how much I gathered in the first year, but we easily pulled out 10,000 pounds in each of the last 2 summers. The problem seems to be getting worse, not better. The only real benefit we’ve seen from this is we went from almost no visibility in the water to the approximately 18 inches we now have. Fishing has been near impossible, so we have no idea of our fish population other than we have a mix of LMB, BG, catfish and grass carp (20 placed in 2010 and another 30 placed in 2012)

We know we have a nutrient problem, but now we need to find a way to correct it short of draining it and dredging it out. We have a couple of sewage lagoons that discharge into our watershed, but for the last two years when the plant life was at a peak, we were also having a drought, and there way were we getting any of the discharge. My current working theory is that the drought concentrated nutrients and released more nutrients due to bottom action from the fish and when we’d get turnover from temperature changes.

One thing we are trying is some Biohaven islands we bought from Martin Ecosystems but we didn’t get started on them until the end of August. Each one is 70 sqft and they are both planted with Blue Flag iris, juncus effuses (soft rush), carex stricta (tussock sedge) and pickerel weed. After reading some articles on this forum, I decided to move some of my aerator heads up by our dock and leave the islands there so they don’t freeze up this winter. We live in Warrensburg, MO and if you want to see a picture of our pond at the end of the worst drought in 2012, just look up 260 SE 581 Rd. We’re the biggest green blob in the picture even though it looks more like a sewage lagoon

Right now my plan is to continue aerating, even though I think it is stirring up nutrients from the muck. I’m think about get a few more 6in diffusers and working with multiple diffuser in one area while I walk around and stir up the muck. I bought a drysuit so I can start gathering remaining coontail early in the spring, which should also make the aerators work better. I’m also thinking about getting some plastic pontoons to make a barge so we save time over having to pump out the boat each trip. Lastly, even as much as I have tried to, I’m afraid we might need to use a herbicide on the duckweed and watermeal. Does my course of action seem reasonable? Does anyone have any suggestions to make things better. Thanks in advance for reading through this and providing any ideas that could help us fight this mess and reclaim our pond.

Do you care about the fish in there right now or will you start over with the fish ?

We're trying to save the fish that are in there. One great thing about the aerators is we avoided a fish kill last summer; many of our neighbors were not as lucky.

Would Tilapia help?

I can't help you because I'm just learning about this stuff. Our pond is new so has not had the time to develop problems like you have but we are already getting FA.

The reason I bring up Tilapia is in some of my reading they are claimed to be very good vegetative eaters. One ad claims that they will do almost everything except walk the dog, but I figured they might be overselling a bit.

I know there are people on this forum that have experience with them and can suggest if they would be beneficial.

Tilapia are illegal in Missouri.

Thanks for the thoughts Snrub, I was real excited when I first read about them, at least until I found out that they are oil legal in Missouri, like John Wann said.

I wish they were legal too. They must think somebody might turn them loose around a cooling station. Seasonal trout pond + seasonal tilapia pond = a no commitment pond that would feed you well.

I'm probably more a naturalist with my pond then most and I experiment letting it become different kinds of ponds over the years. I watched my pond become so thick with Eurasian Milfoil that it was almost impossible to row a boat in it. I ended up putting in 18 grass carp, which really took care of the problem but it took about 4 years. In the end they took out almost all plants, even slightly controlled the cattails. Your GC ratio is about the same as mine, which was 18 GC for my one-acre pond. I like the idea of having some cattails at the entrance of your pond for filter control. The others you will have to spray. I used to have good cattail control when I had muskrats but they left since my dog patrols the pond now.

When I had an abundance of underwater plants I didn't have much FA since they were taking the nutrients from the water. The abundance of water plants kept my water very clear. When I didn't have the abundance of plants because of the GC I then controlled the FA with 20 KOI, 6 Israeli Carp and Channel Catfish for my one acre. My Pond is closed from other water getting in and this worked for me. I had a fish kill but that allow me to start a different kind of pond, so that wasn't all that bad.

I had one winter fish kill and that was because I didn't get down to the pond to remove some snow to allow the sun to start my plants producing oxygen for the fish. So plants for me are oxygenators, fish food, nutrient eaters, structure, FA eliminators and water clarifiers, nature’s way.

One approach is to use the nutrients up with desirable plants. We have a natural edge on our pond with no cattails. A similar plant that is better behaved is burreed. We have a great diversity of plants which has worked very well for us. I have read that one needs to go easy with grass carp. It takes a while (years) for them to do their job, so it is common to over stock.

BWH, I am close to you, just down in Windsor. I had a bad Water Primrose issue the second year my pond was filled but NO FA. I killed all the primrose and the following year, my FA positively exploded! I have row crops and cattle in my watershed that I can do little to stop, similar to your lagoons. I have planted pickerel weed, arrow root and allowed the primrose to come back some and the FA is definitely more controlled. I also use some dye to help with cutting down the visibility. It all helps. The floating islands you mentioned should help, for me, I have found that I would rather have just about anything than FA as far as vegetation. Good luck! People on here can offer a lot of different ways to help you tackle your problem based on your wants for the pond. I wouldn't give up on the aeration systems, they take a while to help with the muck and have other benefits too. Happy Thanksgiving! CMM

Thanks for all the responses so far. Coontail, if controlled, is actually a good oxygenator and fish food. Right now it is way too much and it fouls the prop on our trolling motor in many parts of the pond and makes fishing impossible unless you're trying to get your coontail limit. The hope with the islands is that they'll take up nutrients faster than the native plants in the pond and allow me time to harvest much of the coontail. It is challenging dealing with the evolving nature of the pond, and more importantly, knowing where to spend your money to get the best affect. I definitely haven't given up on aeration, but now I am going to more actively move diffusers to try and work off muck in different areas of the pond. Thanks again and hope y'all have a great Thanksgiving!

Brian

To begin, filamentous algae is easily recognizable, but are you positive that your weed problem is coontail and not some other weed species? Coontail is a plant with no true roots, thus most of it grows as weed masses hanging in the water column and not attached to the bottom. Regardless your pond has a lot of it.

Your pond is once again proof that aeration, even very good aeration, will not overpower the effects of heavy nutrient enrichment and weeds that include filamentous algae and submerged weeds. IMO your pond should be "poster boy" for people who think or are told that aeration will solve all their algae problems.
https://maps.google.com/maps?q=260+SE+58...ved=0CCkQ8gEwAA

Often in situations where nutrient concentrations are "on the fence" between low and mild (early or middle age pond), aeration can appear to be a significant deterrent to algae problems. And in these instances is where the whole idea of aeration controlling plants (algae) 'sprouted', although IMO it is an erroneous concept. Push the nutrients to the next higher level and the best aeration fails. Then supplemental management efforts such as dyes, algaecides, bacterial (microbe) additions, submerged rooted plants, and a few other natural methods are needed to keep the pond from being overgrown with nuisance plants. Accumulation of even more nutrients requires more and more of the previous abatements until when using all those combined seem to have little impact on the rampant growth of plants.
Eliminate one nuisance and another form appears. 'Mother Nature' demands that something will grow in the over enriched, hyper-eutrophic, nutrient 'soup bowl' called a pond. Duck weed and watermeal are two plant indicators of over enriched conditions. In these situations not much seems to work or 'clean things up' at least for very long.

I do not relish sounding negative, but laws of Mother Nature are often not kind nor politically correct.
Regarding the floating islands and if they will be effective, Have you spoken with Bruce Kania at Floating Islands International (FII) about the necessary amount or surface area of FI that are needed per acre to abate your nutrient soup pond? Have you conducted any nutrient tests to determine the amount of nutrients that need to be absorbed, processed, or sequestered each year? I think for FI to work effectively, one needs to know how many nutrients available need to be sequestered and then use the appropriate amount of FI sq footage to get the job accomplished. I am sure that it is known by FII approximately what each sq ft of FI can accomplish in nutrient sequester per growing season. I suspect from seeing the amount of plant growth in the picture above that the cost for the adequate amount of FI will be quite high.

Considering what you have spent in time and manual "LABOR" to date for plant control and what you will spend in the near future my advice is to plan in the near term a pond renovation where elimination of sewage discharges and thick nutrient bottom sludge will make a world of difference in the amount of annual nuisance plant growth. Aeration investment is usable in any age of pond, new, renovated or old. Other investments such as bacteria and chemicals, etc. are lost and not good long term investments since they are temporary fixes.

Ponds are catchment basins, especially those that are sediment traps with high nutrient inputs and have minimal flushing (long retention times). As soon as ponds/lakes are excavated and filled with water, Mother Nature's plan is to fill them back up with muck and sloppy sediments until they are a swamp and then back to dry land. It is called aquatic succession. We pond owners try as much as possible to slow and delay that process. In situations where poor design and poor or no management prevails, the aquatic succession happens fairly quickly due to high nutrient inputs and excessive annual plant growth. Thus a pond such as this one, built relatively recently as a nutrient accumulator and enriched sink are after a fairly short time over enriched and a plant infested mess for lack of a better term.

There are no magic bullets to my knowledge (wish there were) for a pond in the current condition. I doubt that you will get any guarantees for any of your "pond fix" investments. For your long term plan, I suggest that you investigate prices or bids for good, skilled, wisely planned, pond renovation for your situation. A renovated pond does not have to be as big as the current pond. Spoils from rebuilding can be stored in some of the current bottom areas thus rebuilding does not have be as expensive as building an entire current size. Get that body of water back to new condition with wise nutrient, watershed management, that at the end, includes bottom aeration and then you will have a lot fewer headaches, less aggravation and fewer sore mussels. Then you will have an enjoyable water resource instead of a continual low water quality, plant infested problem.

Thanks for the in-depth response Bill. I've attached a picture with coontail. Yes, it is big rafts of plants that aren't attached to the bottom. We sent water in for testing, and I'd attach the pdf report, but I'm not sure how to do it. The test didn't show any major nutrient issues, yet clearly we have them based on the amount of plant life we have. I'm thinking that the aeration and maybe grass carp and catfish are stirring up the muck layer and consistently providing nutrients to the extensive plant life. I feel this way because we've had a drought the last 2 years, so other than a couple of flooding instances this summer, no additional nutrients have been introduced from the watershed.

In an ideal world, we'd have the money to drain, dig out the muck, and start all over again, but in my world I doubt I can afford that. We did not talk to Bruce Kania, but we've been working with the distributor for our area, Martin Ecosystems. Our hope is that the plants in the island will out-complete the other plants for nutrients. That is also why we're considering a few more islands. I think the islands, manual harvesting, selective herbicides for duckweed and water meal, and aeration are about the best I can do now with the funding constraints I have.

I agree, there are no magic bullets or guarantees, but I think the plan of action I'm considering will get me back to balance in the next few years. Please let me know if I'm missing something other than draining and starting all over again. Also, let me know if you're interested in seeing the lab report; I could forward it to your email. Thanks again for the great response.

Brian

Plants in the water do look like coontail. I would be interested in seeing the report of water testing. Send it to my email address listed the my profile. When water is collected during large amounts of plant growth it may not show many nutrients due to the large amount of plants have about all of the current amount of dissolved nutrients bound into plant matter. However those plants did not grow in lack of nutrients. Coontail often overwinters as green dormant plants which allows it to get growing early in spring before other warmer water species. One approach may be to use a herbicide early in spring (water temp 50-55-60F) and kill existing plants and new growth. Coontail regrows from winter buds so one should treatment to be a 2-3 yr project. Concern with this approach is, as best as possible, target just the coontail and not other beneficial competing plants that happen to be present. Treatment may need to be applied earlier than 55F before other plants are newly sprouting?. When most or all coontail is killed the FI and other nutrient absorbers should be in place to sequester nutrients. Once coontail is minimized the grass carp should be able to keep it trimmed to low or no density. When a pond has too many grass carp (GC) expect the clarity to be reduced likely around 14"-2.5 ft depending on number of GC. Reduced water clarity has a suppressive affect on rooted plant growth due to lack of light penetration which is not all bad for shallow weed-algae infested ponds.

I would regardless still contact Bruce Kania at FII and ask what density (sqft/acre) that he uses to sequester his eutrophic nutrient laden 6.5 ac pond. He uses a big fish harvest per year to remove bound nutrients. See Pond Boss Magazine Nov-Dec 2013 - Fish Fry Lake - A deeper testimony to using natural nutrients. He should at least communicate with you about your situation since you do already have some FI. He also has submerged weeds in his pond but I do not know the species nor the amount (% coverage and depth of growth).

I would at least get a quote for rebuilding the pond so you know how much money to budget for. Sooner or later it will have to be done regardless of who owns the pond. You are experiencing one of the big disadvantages of owning a pond that is too shallow and too big.

I'm sure Bill and others have covered this, but taking out the coontail might make the FA take off instead. I can fish through coontail with many different kinds of lures. I've yet to come across a good lure for fishing through an algae mat

Actually no one has mentioned that as a possibility, but I can see where it could be. We had some challenges with FA, but the coontail has made the water unnavigable in places; we just get large globs of coontail fouled in the weed less prop on the trolling motor. We're hoping the islands become more of a nutrient sink, then there's always the duckweed and water meal. Would you share what works well for you in coontail ; I doubt we'll ever get rid of it all.

BWH, your story sounds very similar to mine. I moved here March 2012 to find a very old pond, 12-18" of stinky muck, riddled with FA, Coontail and a complete blanket of DW. Rowing was out of the question, let alone a trolling motor.

The pond is 2 acres averaging 4' deep except for a 9' channel the length of the dam.

Initial treatment of pond dye, Cutrine Plus (liquid and granular) in April for the FA, Vertex aeration system in May, and followed up in July with Alligare (Fluridone) for the Coontail and DW. By September 1st my pond was DW free, with the Coontail dead and dying (as well as most other vegetation). As told could happen, the Coontail reappeared this year so I treated again with Alligare in the Spring. BTW, I also stocked 8, 12" Grass Carp 10-1-12 and they are now HUGE, and hopefully keeping any new CT in check.

I was aware I could be trading the DW and Coontail kill-off for an explosion of FA but I got extremely lucky to have hardly any at all this year. My guess is due to pond dye (though none added since spring) and a great plankton bloom leaving water clarity at 12-18" pretty much all year.

This is a recent photo and if you look closely you can see the 4 bubblers (diffusers).

All year I've enjoyed weed-free trolling and fishing!

I'm not suggesting you take the same path, as the folks here certainly know more than I do, I just wanted to share a similar story. Fortunately I've had excellent results and now have a pond that I and many family and friends have enjoyed all year.

Keep gathering info and keep the faith!

PB Rocks!

L-livin has the concept correct. Generally or almost always some type of plant will utilize the available nutrients - often it is several types or species of plants. Killing one often results in a surge of the other plants. Ideally one would want that plant surge to be beneficial phytoplankton. There are nuisance species of phytoplankton - mostly Cyanobacteria - aka bluegreen algae. Sometimes as in L-livin's case the grass carp ate the plants with roots and phytoplankton flourished to make water still plant productive but with low water transparency due to phytoplankton.

That being said, I just shut down my aeration system on Sunday (the deep one has been off since November 1st) as I want the pond to ice-over so I can access the dam to clear the brush off of it and do some ice fishing. I'm now wondering if the plankton will die with the cold tempertures and cause a DO sag or crash.

My pond is healthy, the fish are healthy and have grown well, yet with the Fluridone treatment and lack of vegetation (plant-life), a fish-kill would be devastating after getting this far.

Is this or should this be a concern and would I be better off leaving at least one diffuser going, other than to open some water if there's snow cover?

If the water cloudiness is truly due to phytoplankton and not suspended sediment from activity of grass carp going into ice up then extended snow cover, under ice darkness and loss of abundant phytoplankton will cause a significant DO sag. If you have enough thick ice for ice fishing then I would make an effort to remove 25% of the snow if you don't have at least one aerator operating in shallow water (5-7ft). The pond no doubt has extensive organic sludge which is a big oxygen consumer 24/7. In winter DO loss starts at the bottom and works its way toward the surface. Clear snow free ice will allow oxygen production during sunny days about twice as deep as the light penetrates through the ice and underlying water. Under clear ice and sunny days phytoplankton will increase DO concentrations of 4 to 6 ppm per day and after several sunny days DO will become supersaturated to the depth light penetrates.

Thanks for the encouragement Lovnlivin, it appears that our situations are quite close. I spoke with a local pond management firm recommended by members of this forum. He recommends fluridone at 90ppm next spring coupled with more aggressive bacteria and aeration and feels we should have a pretty usable pond by the end of summer, maybe sooner. Retreatment with fluridone will be done as needed based on plant growth and it will also depend on how much outflow there is.

Bill Cody, I talked with Martin Ecosystems, and they are my local distributor for Biohaven Islands. They have access to all the calculations that Bruce Kania does, but as you state, getting enough islands to offset my nutrient load would indeed be cost prohibitive. It looks like Bruce had a little over 2% coverage of islands from an article I read on the Biohaven website. I need to ask a neighbor what he paid for pond renovation, but the local management firm thought I'd be doing good if I could get it done for around $50,000; also cost prohibitive.

I've got some time, so I'll use it to do some more research. I knew a swimming pool was costly; I never realized all the challenges associated with a pond.

Pond renovation can be significantly less if the pond is down sized and spoils are spread into shallow weed prone areas. One acre of water is a lot to manage properly, cost and labor wise. Large is not necessarily better especially if the pond is shallow, nutrient rich, and prove to excess plants.

Bill Cody, would you skim off the top nutrient layer and deposit it out of the watershed and then deepen an area closer to the dam as far out as you wanted while placing the spoils in the shallowest areas furthest from the dam? If you didn't skim the nutrient rich muck and deposit it outside the watershed, would you run into problems with the nutrients going back into the renovated pond? If a person were to do something like that, what is a good depth to shoot for, and do you recommend a 3 to 1 slope on the edge of the pond. This is an idea we had not considered, but I can see where it would be much less costly than trying to dig out the entire BOW and transport the spoils elsewhere.

Various ways to deal with spoils and rebuilding or reshaping the pond basin. Initial goal I think would be to push out all accumulated sludge down to original pond basin and maybe excavate more depth to the downsized pond. The steeper the slopes (3:1 or 2.5:1) and deeper average depth the fewer weeds a pond tends to have. Keep in mind that steeper slopes mean more dirt needs to be removed thus more expense per acre of water. IMO a smaller easier to manage pond is a lot better to have and deal with than a large unmanageable, nuisance prone, poorly designed pond.

Spoils (removed sludge-muck) can be graded and vegetated so water runs away from the pond. Watershed drainage could be from specific areas that contain primarily water with low nutrient loads. A well rebuild smaller pond with optimum clay compaction and steep slopes with minimal seepage takes less water to keep it full due to low volume leakage compared to a seepage prone pond.

The local Soil and Water Conservation District engineer or regional soil scientist might be available for a site visit and a free opinion for your situation due to a desire to better manage the nutrients in the water shed. It is worth a phone call. If you explain your goals to a good pond builder he should provide several good options.

When water fertilization is part of the management, starting a pond as new and using fertilization to minimize nuisance plant growth is a lot easier, more predictable, more dependable due to more control of the overall nutrient budget. Duckweed, since it is a symptom of thick organic sediments and excess fertility, rarely grows in newer or even middle age ponds with 'average' nutrient loads. In an old pond with thick sludge and an unknown amount of nutrient inputs from internal recycling this makes it more difficult to manage or control the entire nutrient budget necessary for maintaining an optimum phytoplankton community so there is a dependable and consistent nutrient bloom to minimize the rooted weed and FA growth in large areas of shallow water. Ponds with deeper average depths, and lower nutrient loads rarely need fertilization to produce dense plankton blooms to manage for reduced FA and weeds.

Thanks Bill Cody, lots to think about before we reach a decision!