Pond Boss
Hi everyone! I'm George & this is my 1st post here.

I have a question but the info I've read here isn't specific to my conditions, so, I thought I'd post.

We have a pond only because we needed soil to fill around our new built retirement home in Michigan. We really didn't want a pond because I don't fish & we didn't want to spend our retirement cutting cattails & raking algae out of it which we did the first few years. But, we need back fill so we wound up with one.

The pond is bean shaped, roughly 150' x 90' & 15' at the deepest. The pond is 100% rain water feed; no streams feed into the pond & overflow only drains in the spring. In the late summer the water level falls several feet.

The soil dug out for the pond was grey clay. Nothing would grow in areas where this clay is spread around the house. We needed topsoil brought in just get to grow grass. And because the pond soil is clay based, I doubt if anything seeps very deep into it.

A few years ago I mentioned to a local farmer that we spent a few days cutting cattails & raking algae. He laughed & recommended Karmex (Diuron 80), that he used it all the time. The local co-op who sold it said with my conditions (a clay based pond where no water was flowing into or out of it) was OK.

When I 1st used it, it was windy & some did get on the grass as a powder. It killed grass everywhere it touched. I had to shovel those areas out & replace the soil & grow new grass. Since then, I have mixed in water, then splashed it into the pond. I also learned to wait until the pond stops draining (late May) before using Karmex, so, water treated with Karmex never flows out of the pond.

I guess my question is why wouldn't using Karmex be OK under my conditions? My pond is clay based. Grass isn't dying near the pond. Trees nearby are fine, nothing is dying. Unlike my farmer neighbors who spray their fields with Karmex, which is eventually washed into the great lakes nearby, my pond water stays on my property.

So, why wouldn't using Karmex be OK?
Any fish in the pond? And eventually it will kill trees that feed from the pond.. I've seen it kill many trees.. I think copper based herbicide and algaecide would be better for you..
Very simple answer, there is no label for your particular use, with the label being the law it makes your application illegal.All ponds leak to some degree so its going somewhere.
Originally Posted By: Bluegillerkiller
Any fish in the pond? And eventually it will kill trees that feed from the pond.. I've seen it kill many trees.. I think copper based herbicide and algaecide would be better for you..


Thanks.

No fish. Our property didn't have a tree on it until we moved in & we have planted 65 large trees, some shade, spruces & pines. There are white pines recently planted about 30' from the pond. There's a linden near the pond as well with no signs of problems.

My only objective is for my pond to be free of algae & cattails. Is there a particular copper based herbicide and algaecide you'd recommend?
Originally Posted By: Ted Lea FOREVERGREEN
Very simple answer, there is no label for your particular use, with the label being the law it makes your application illegal.All ponds leak to some degree so its going somewhere.


1st, the pond is there because I put it there.

2nd, this isn't a "natural" pond, as I have pointed out. Only rain water & snow melt flows into it. Only in the early spring does anything flow out & then it flows about 200' to an accumulation area, never moving from there.

3rd, I learned recently that it was illegal & have not used the product since. But algae is coming back so I need to do something.

What I don't understand is how tons of this product can be sprayed legally. Eventually it rains & washes into somewhere other than where it's intended. Certainly my using a 4# bag illegally in a contained area is dwarfed tons used legally.
Originally Posted By: GARoss
What I don't understand is how tons of this product can be sprayed legally. Eventually it rains & washes into somewhere other than where it's intended. Certainly my using a 4# bag illegally in a contained area is dwarfed by tons used legally.


I've wondered the same thing GARoss.

In fact I've heard all the horror stories about it, causes cancer..ect. Then I read where Mississippi actually got a waiver from the EPA to use Karmex to control algae in catfish ponds that raise catfish for human consumption. Go figure!

http://deltafarmpress.com/livestock/herbicides-approved-fight-pond-algae

Our caretaker last fall used Karmex without our permission and made our pond practically as clean as a swimming pool when it was filled with algae and aqautic vegetation. We told him to never do that again. Luckily we did not suffer a fish kill because he used very small amounts. And this spring our pond is filled with bluegill and lots other fish. Appears healthy as ever. We dont eat fish out of the pond anyway. I wish Karmex didnt have the downsides because it sure works fantastic, is cheap, and so easy to use for cleaning up a pond. I am using Cutrine Plus this year.

First welcome to PB.

There are other products. I know a guy who killed his prized (large adult) walnut trees by doing what you ask about. These trees were 100+ years old and were a min of 100 feet from the pond(some were 100 yards away). By the time he knew he had a problem it was to late.
Rodeo for cattails, Cutrine Plus for algae.
70 mph is legal on some roadways, while 30 mph is illegal in others.
There's a big difference between highways and city-streets - and terrestrial and aquatic sites; especially with chemistry half-lives, and from a long-term environmental impact perspective.
Will you own your pond forever? Will future owners of the property consider stocking it with fish, or use it to water livestock, or irrigate a garden - or for potable purposes as water-scarcity increases?
Black helicopters probably won't swoop in out of nowhere with camo-clad EPA officials aboard if you do something you really shouldn't. But, just because you don't get ticketed or cause an accident while speeding down a roadway doesn't mean it's safe to do so.
As for me, I definitely wouldn't use it in any pond under my control.

Zep: the "EPA waiver" in MS (and TX) was politically driven by commercial food-fish producers (it's called a Section 18 Emergency-Use Exemption) - and has no toxicological data to support such uses. Check the Sect-18 guidelines. 0.8 oz per acre-foot is the permitted dosage for controlling a specific form of algae that causes off-flavor in fish (but is insufficient for weed or filamentous algae control).
Thanks Kelly. My former caretaker I think said he put a teaspoon every 12-15 steps around my 4 acre pond. It was utterly amazing how it cleaned the pond up. With no fish kill that I could see and I've got tons of action in my pond this spring. But I was told it messes with the bottom of the food chain, so I told him to never do it again. But still isn't it amazing if this stuff is really that bad that it would EVER be approved in any amounts for commercial catfish farming that may end up on your table at Red Lobster?
Originally Posted By: Zep
But still isn't it amazing if this stuff is really that bad that it would EVER be approved in any amounts for commercial catfish farming that may end up on your table at Red Lobster?


That's why I almost NEVER order fish when at a restraunt. Last time I ordered fish it was fresh, never froze Bluefin Steaks that were seared over Mesquite and *barely* cooked inside the center of the steak.
I bet much of what we order fish or whatever is full of chemicals
and many of the items at the grocery stores. Sad
We used karmax for years working for the state in city parks.. It was used for approximately 5 yrs and killed roughly 75% of the trees within 50' of the waters edge., and I'm talking huge healthy oaks I'm not 100% sure this is what killed them but they lived perfectly for 100's of years before spraying.. This stuff is bad news but works great basically instant death of FA..
you sprayed it?
Writing a book? Leave this chapter out. smile
I'll add one more thought to contemplate.

DuPont was the discoverer and original producer of diuron; back in the 60's I believe. Over the decades, DuPont pursued and received countless EPA registrations for diuron in a wide variety of terrestrial applications - and sold millions, possibly billions of pounds in the process. Yet, DuPont never, ever sought a diuron registration for aquatic use (a fact that most folks don't realize).

Now ask youself: Why would a large global company, with plenty of resources, decide to ignore an otherwise lucrative market-segment (aquatics, of any nature) for one of their flagship products?
Lackluster efficacy certainly wasn't an issue!

Let me know if anyone comes up with an answer that provides any sense of rationale or comfort for applying this product to your pond.

PS: Approximately 4 years ago, DuPont completely divested themselves from the global production and marketing of diuron (aka Karmex). Food for thought.....
Thanks for all the info Kelly. As usual you're a walking encyclopedia on the stuff! (not that you have any experience with weed control........) wink
Politics controls everything. crazy While we were building we were hit up by the DEQ (Department of Environmental Quality) for a permit because we had "disturbed" 2 acres of soil. Huh? Like we're going to build a beautiful home & not grow grass? It seemed the pond digging pushed us over 1 acre which would of been exempt.

"So, $720 for what?" I asked DEQ.
"Well," DEQ replied. "Because you're within 500' of a drainage canal to Lake Huron. All this loose soil can drain into the canal unless the vegetation is restored."
"But all my land slopes in the opposite direction of that canal. It's impossible for rain water to flow uphill into the canal."
"It doesn't matter, you disturbed soil within 500'".

We paid for the permit & a year later received a 50% refund. But, all we did was build a home. Hundreds of thousands of acres are farmed each year. Tons of fertilizer, pesticides & weedkiller are used - all legally exempt, & all that flows into the lakes, too. I'm all for farmers but I don't understand the politics of the DEQ. How could I be charged for a permit for 2 acres & no chemicals & farmers exempt?

I've seen some suggestions of products other than Diuron & I will try one. My goal was to clear the pond, not kill our environment! grin

Thanks everyone!
GARoss believe me we hear you and many of us have had (or are having) the same problems.

Our job here is to help give answers (provide the knowledge) not make any decisions (those are best left to the informed landowner).

We stay out of politics here because all hell would break lose if that can of worms was opened. Plus it is against Forum rules for that reason.

There ae other threads here on both EPA/COE and karmex if you want to read them.
Originally Posted By: Zep
I bet much of what we order fish or whatever is full of chemicals
and many of the items at the grocery stores. Sad


Not true if it comes from the U.S. However all bets are off if it's imported farm raised.
Originally Posted By: ewest
GARoss believe me we hear you and many of us have had (or are having) the same problems.

Our job here is to help give answers (provide the knowledge) not make any decisions (those are best left to the informed landowner).

We stay out of politics here because all hell would break lose if that can of worms was opened. Plus it is against Forum rules for that reason.

There ae other threads here on both EPA/COE and karmex if you want to read them.


Well said! And I will add that everyone here has been most helpful & understanding as well. I must apologize for the political rant! blush

I believe in saving our planet in anyway that I can help. I spoke to Applied Biochemist this morning & the rep in Cleveland, Tennessee helped me identify the type of algae (she wanted to make sure it wasn't duckweed) & which of their products would be most effective. Cutrine Plus liquid is on the way.

My thanks to all & please accept my apology.
Originally Posted By: Cecil Baird1
Not true if it comes from the U.S.


Cecil...I'm not so sure.
Don't take me wrong...I eat meat,
but our diets with hormones/chems here in the US scare me.

"Russia announced that it intends to ban US imports of beef and pork unless these foods can be certified free of the livestock drug ractopamine"
http://thefern.org/2012/01/dispute-over-drug-in-feed-limiting-u-s-meat-exports/


"ammonia-treated meat paste that appears in some
70 percent of supermarket ground beef"

http://gothamist.com/2012/03/19/beyond_the_pink_slime.php


"U.S. standards on beef are lax, inspector general says"
"In 2008, Mexican authorities turned away an American shipment of beef, because it did not meet Mexico's limits when tested for copper traces. But the very same rejected meat could be sold in the United States, since no limit has been set, the analysis says"


http://www.cnn.com/2010/US/04/14/us.beef.testing/index.html


"Beef produced in the United States is heavily contaminated with natural or synthetic sex hormones, which are associated with an increased risk of reproductive and childhood cancers, warns Dr. Samuel S. Epstein, Chairman of the Cancer Prevention Coalition." http://world-wire.com/news/0910210001.html
Karmex works to sterilize the pond of plants just as a nuclear bomb works to eradicate life, but is it wise to use either product? Dupont no doubt knew the destruction Karmex had on the aquatic food chain which is probably why they never bothered to try and get it registered for aquatic use.
He might have been referring to the fish part of that comment Zep, not sure that just kinda how I took it..


Originally Posted By: Zep
Originally Posted By: Cecil Baird1
Not true if it comes from the U.S.


Cecil...once again...we will "agree to disagree".

"Russia announced that it intends to ban US imports of beef and pork unless these foods can be certified free of the livestock drug ractopamine"
http://thefern.org/2012/01/dispute-over-drug-in-feed-limiting-u-s-meat-exports/


"ammonia-treated meat paste that appears in some
70 percent of supermarket ground beef"

http://gothamist.com/2012/03/19/beyond_the_pink_slime.php


"U.S. standards on beef are lax, inspector general says"
"In 2008, Mexican authorities turned away an American shipment of beef, because it did not meet Mexico's limits when tested for copper traces. But the very same rejected meat could be sold in the United States, since no limit has been set, the analysis says"


http://www.cnn.com/2010/US/04/14/us.beef.testing/index.html


"Beef produced in the United States is heavily contaminated with natural or synthetic sex hormones, which are associated with an increased risk of reproductive and childhood cancers, warns Dr. Samuel S. Epstein, Chairman of the Cancer Prevention Coalition." http://world-wire.com/news/0910210001.html
GAR: I would love to see that local co-op manager's face if an inspector for your state dept of agriculture walked into his store and asked for the person who was recommending diuron for aquatic treatments; or your farmer-friend's face for that matter.
I can assure you, their smug attitudes and winking smirks would disappear in a heartbeat.
I'm betting that the farmer would never contaminate his crop with a non-labeled pesticide: which begs the question, why would he do otherwise with his own pond - or encourage his neighbor to commit the same blunder. Evidently, he considers himself smarter than an impressive number of highly educated research chemists and environmental toxicologists.
To paraphrase an old Will Roger's quote: -That which we don't know rarely gets us into as much trouble as what we know, that simply ain't so.-

Bill: Interesting analogy, and quite accurate.
Originally Posted By: Bluegillerkiller
He might have been referring to the fish part of that comment Zep, not sure that just kinda how I took it..


But it's already been shown that US commercial catfish farms in Miss. (and possibly Texas per Kelly Duffie) have and do sometimes use Karmex in their ponds. One would think many US restaurants and US grocery stores are buying catfish from US catfish farms in Tx & Miss.
Just to balance things a bit - think where we would be without chemicals. Likely about 2/3 of us would not be here. Starvation and other natural processes can easily take out man or greatly reduce the population.
Originally Posted By: Kelly Duffie
GAR: I would love to see that local co-op manager's face if an inspector for your state dept of agriculture walked into his store and asked for the person who was recommending diuron for aquatic treatments; or your farmer-friend's face for that matter.
I can assure you, their smug attitudes and winking smirks would disappear in a heartbeat.
I'm betting that the farmer would never contaminate his crop with a non-labeled pesticide: which begs the question, why would he do otherwise with his own pond - or encourage his neighbor to commit the same blunder. Evidently, he considers himself smarter than an impressive number of highly educated research chemists and environmental toxicologists.
To paraphrase an old Will Roger's quote: -That which we don't know rarely gets us into as much trouble as what we know, that simply ain't so.-

Bill: Interesting analogy, and quite accurate.


The farmer who recommended Karmex has since moved.

I no longer deal with the store I 1st purchased Karmex from. He never mentioned any law about using it in water even though I told him I would use it to kill algae in my pond. When I asked how to apply it he said to spread it "like you would feed chickens". I did; but unfortunately on a windy day. Some of the Karmex power blew onto the grass near the pond's edge & killed patches of grass where the Karnex power hit! I couldn't grow grass in those areas until I dug out & replaced the top soil.

I bought Duiron 80 from a different store the next year but didn't mention how I was going to use it until this year. That's when clerk immediately told me it was illegal to use in ponds. No problem, but it got me wondering why farmers could use it, etc & to post on this forum.
Originally Posted By: ewest
Just to balance things a bit - think where we would be without chemicals. Likely about 2/3 of us would not be here. Starvation and other natural processes can easily take out man or greatly reduce the population.


very true eric
Originally Posted By: ewest
Just to balance things a bit - think where we would be without chemicals. Likely about 2/3 of us would not be here. Starvation and other natural processes can easily take out man or greatly reduce the population.
Eric: It goes without saying (I hope) that I'm a strong proponent for the legal, appropriate and judicious use of pesticides - especially since they represent my livelihood.
Because of that; and since I'm fully aware of what it now costs to bring a new product to market – as well as the battles that my industry faces with "anti's", I'm very sensitive to any and all pesticides-abuses, which are often used to slam the entire industry when things go wrong.
Example: Chlordane. Widely abused in the 70s-80s as an ant mound & exposed ground treatment - which led to environmental/water contamination issues that probably would not have occurred had chlordane’s uses been confined to sub-slab termite treatments (as per label).
As a result of chlordane’s abuse, besides the environmental issues, we now get to treat our homes and structures at least once every 5 years for termites, with much less effective insecticides – instead of one time with chlordane (with its 40-year half-life).
Kelly, 2 years ago I cleaned out my grandmothers basement. You wouldn't believe what I found (well, you probably would).

Clordane, DDT, etc. One can is marked Bug Pizen (not a typo). I'll take a pic tomorrow after I get back from Mi. delivering fish. Camera is in the truck and I'm beat.
The rep from Applied Biochemist, makers of Cutrine-Plus, recommended 14oz per 1 gallon in my sprayer. Early last week I ordered Cutrine-Plus online + a separate sprayer for it. It finally came in & I tried some yesterday & have some early results. Everywhere the sprayer could reach is browned out - perhaps 10% of the algae.

For those who have used Cutrine-Plus, will the dead algae sink to the bottom or does it need to be racked out?
I haven't been raking mine out, but I suppose it may be best if you do.

Course if we're gonna rake it all out, maybe we didn't even need the Cutrine Plus?

I'm too lazy and it's getting way too hot in Texas for me to be raking it out.
Originally Posted By: GARoss
For those who have used Cutrine-Plus, will the dead algae sink to the bottom or does it need to be racked out?
Ideally, one would rake out (or otherwise physically remove) as much FA as possible before treating - if so inclined - and relocate it (after it dries out) beyond the pond's watershed - and then treat any remaining patches of FA with Cutrine. By using this approach, the nutrients bound within the algae are removed from the pond - and the need for and usage of CUTRINE is reduced. That's a win-win scenario.
In your present situation, physically removing the dead algae at this point will accomplish only one of the mentioned benefits. However, if you leave it undisturbed, it will eventually sink once the FA's bouyancy-inducing bubbles become dislodged; at which point, the release of nutrients from the decomposing algae will likely spawn a new generation of FA from ever-present spores.
This morning I noticed the un-sprayed algae didn't look as bright green as it did before spraying.

I'll rake it out.
Originally Posted By: GARoss
This morning I noticed the un-sprayed algae didn't look as bright green as it did before spraying.

I'll rake it out.


A combination of rain & busyness prevented me from raking out the dead algae but not to worry - the algae is gone! It sank to the bottom! Three days is all it took & I only spray about 20% of the algae to do it. Nice to know there are products that are environmentally safe!

Thanks to all for the great advice you shared.
I have been reading these posts, and I am surprised no one has mentioned that Canada allows the use of Karmex in ponds, or that Miss. has recommended the use in catfish ponds since 2005
as seen in this:
Herbicides approved to fight pond algae
Jun 13, 2005 Delta Farm Press
EMAIL
INSHARE



COMMENTS 5
Mississippi Agriculture Commissioner Lester Spell recently announced his department has received approval from the United States Environmental Protection Agency for an emergency exemption on the herbicides Direx 4L and Karmex DF (both diuron) to control blue-green algae in catfish ponds.

“Our effort to make these diuron products available as pond management tools is vital to the health of our catfish industry as it gives producers the needed tools for controlling blue-green algae, a primary cause of off-flavor,” Spell said.

Mississippi catfish producers must balance their need to control blue-green algae with the desire to preserve pond plants that provide oxygen and keep water clean.

Several copper-based algaecides registered for use in catfish ponds are non-selective and have the potential to kill both beneficial plants and non-beneficial plants in ponds.

Direx 4L and Karmex DF are selective herbicides and target the primary pest plants responsible for off-flavor. The species of blue-green algae responsible for significant off-flavor problems in catfish is

Oscillatoria chalybea. This species releases a chemical compound known as MIB (2-methylisoborned) into the water.

Catfish absorb MIB into their bloodstream as water passes through their gills. The compound is transported by the blood and deposited into the flesh of the fish.

Low concentrations of MIB produce a musty-to-muddy off-flavor color, which inhibits the marketability of the fish.

Producers incur considerable costs holding affected catfish in ponds for several weeks until the fish purge the compound from their bodies.

The department has authority under Section 18 of the Federal Insecticide, Fungicide and Rodenticide Act to obtain an emergency exemption for a non-labeled use of a pesticide if significant losses of an agricultural commodity are likely and alternative, registered products are not available or effective.

The department administers the provisions of emergency exemptions through the Bureau of Plant Industry.

Catfish producers with questions can call the bureau toll-free at 888-257-1285.

I do have friends that use this, a little goes a long way, and have had no problem with it. It is not legal, but there you go.
Not legal, is the problem.
Plus without instructions on the bag for dosage, one is guessing how much to use and very likely they are adding too much which results in too much chemical that ruins the food chain for the pond. Plus the excess chemical in the pond will be toxic to people using and animals including dogs drinking the water.
MS and TX both issued Section 18 "emergency use exemptions" for specific diuron formations; but ONLY for use in "commercial" catfish and striped bass production operations, and ONLY at the rate of 1/2-oz per acre-foot of water to control Giosmin (a specific algae that causes "muddy" off-flavor in catfish. The emergency-use exemption also allowed a maximum ANNUAL dosage of 4.5 oz of product per acre-foot.

The Section 18 emergency exemption DID NOT apply to private, recreational fishing, livestock or ornamental ponds (or any pond from which I will knowingly consume the fish).

I'm unsure if either Section 18 remains in effect today. Regardless, I personally declined many opportunities to sell diuron into that sector since I wanted no involvement in the matter - especially 10, 15 or 20 years down the road.

I've heard through the industry that there were several compelling reasons why DuPont (the original patent-holder) never pursued a Federal registration for diuron's use in aquatics - which, by the way, did NOT include the lack of potential profitability. I'll leave it at that.

Let's just say that when something threatens a major state-industry, that industry and their affiliated lobbyists may elect to use political leverage to secure a remedy.

Bottom line: There's a huge difference between EPA "pesticide registrations" and "Section 18 Emergency-Use Exemptions" - and that difference usually involves a shortfall in supportive data for the non-registered product's proposed "emergency use".

Lastly, please cite where you read that Canada allows the use of diuron in ponds. That revelation would utterly astonish me.

=====
Originally Posted By: Funky
I have been reading these posts, and I am surprised no one has mentioned that Canada allows the use of Karmex in ponds, or that Miss. has recommended the use in catfish ponds since 2005, as seen in this:
Jun 13, 2005 Delta Farm Press
COMMENTS 5
Mississippi Agriculture Commissioner Lester Spell recently announced his department has received approval from the United States Environmental Protection Agency for an emergency exemption on the herbicides Direx 4L and Karmex DF (both diuron) to control blue-green algae in catfish ponds.

“Our effort to make these diuron products available as pond management tools is vital to the health of our catfish industry as it gives producers the needed tools for controlling blue-green algae, a primary cause of off-flavor,” Spell said.

Mississippi catfish producers must balance their need to control blue-green algae with the desire to preserve pond plants that provide oxygen and keep water clean.

Several copper-based algaecides registered for use in catfish ponds are non-selective and have the potential to kill both beneficial plants and non-beneficial plants in ponds.

Direx 4L and Karmex DF are selective herbicides and target the primary pest plants responsible for off-flavor. The species of blue-green algae responsible for significant off-flavor problems in catfish is

Oscillatoria chalybea. This species releases a chemical compound known as MIB (2-methylisoborned) into the water.

Catfish absorb MIB into their bloodstream as water passes through their gills. The compound is transported by the blood and deposited into the flesh of the fish.

Low concentrations of MIB produce a musty-to-muddy off-flavor color, which inhibits the marketability of the fish.

Producers incur considerable costs holding affected catfish in ponds for several weeks until the fish purge the compound from their bodies.

The department has authority under Section 18 of the Federal Insecticide, Fungicide and Rodenticide Act to obtain an emergency exemption for a non-labeled useof a pesticide if significant losses of an agricultural commodity are likely and alternative, registered products are not available or effective.

The department administers the provisions of emergency exemptions through the Bureau of Plant Industry.

Catfish producers with questions can call the bureau toll-free at 888-257-1285.

I do have friends that use this, a little goes a long way, and have had no problem with it. It is not legal, but there you go.
Funky...Texas got an exemption and allowed Karmex
for awhile in bass ponds less than ten years ago.

http://farmprogress.com/story-tda-gets-exemption-for-diuron-use-for-algae-in-bass-ponds-9-11986
Originally Posted By: Kelly Duffie
Lastly, please cite where you read that Canada allows the use of diuron in ponds. That revelation would utterly astonish me.

This from Canada but looks to be ten years old:



FOR CONTROL OF ALGAE AND AQUATIC WEEDS
IN PONDS AND DUGOUTS—

"KARMEX® XP is recommended for the control of algae, including filamentous types, and certain aquatic weeds in ponds and dugouts which have little or no water flow-through. For use in water wholly confined to the property of the user, and where there is no outflow beyond the property limits. Treatment is not effective in flowing water. The lower recommended rates control algae for several weeks; higher use rates extend algae control and usually control aquatic weeds such as naiads (Najas), pondweed (Potamogeton), duckweed (Lemna), bladderwort (Utricularia), and Chara. Use at rates of 0.5 to 2 parts per million (ppm) diuron; use the lower rates for algae control and the higher rates for aquatic weeds and for extended algae control"

http://www.tlmltd.ca/assets/pdf/KarmexXP_Label_Eng.pdf
To this old farm boy that stuff sounds more scary than a pic of Bob O. in a pink speedo! I would not want it on my property! eek
Whether is was 10, 15 or 20 years ago, I'm floored that it was actually labeled in Canada. I never knew that!!
Do you know how many aquatic herbicides are registered in Canada today? ONE! That being REWARD (diquat).
Canada is one of the most restrictive places in the world to register aquatic pesticides; which might explain why I'm so surprised to see a Canadian aquatic diuron label.
I'm running this past my Bayer rep for further comment (Bayer bought DuPont's pesticide division around 18-months ago).
Thanks for the link Zep! Although it still doesn't change my personal opinion concerning the use of diuron in aquatics smile
KD

Originally Posted By: Zep
[quote=Kelly Duffie]Lastly, please cite where you read that Canada allows the use of diuron in ponds. That revelation would utterly astonish me.

This from Canada but looks to be ten years old:



FOR CONTROL OF ALGAE AND AQUATIC WEEDS
IN PONDS AND DUGOUTS—

"KARMEX® XP is recommended for the control of algae, including filamentous types, and certain aquatic weeds in ponds and dugouts which have little or no water flow-through. For use in water wholly confined to the property of the user, and where there is no outflow beyond the property limits. Treatment is not effective in flowing water. The lower recommended rates control algae for several weeks; higher use rates extend algae control and usually control aquatic weeds such as naiads (Najas), pondweed (Potamogeton), duckweed (Lemna), bladderwort (Utricularia), and Chara. Use at rates of 0.5 to 2 parts per million (ppm) diuron; use the lower rates for algae control and the higher rates for aquatic weeds and for extended algae control"

http://www.tlmltd.ca/assets/pdf/KarmexXP_Label_Eng.pdf [/quote
]
Kelly, thank you for weighing in with your expertise.
Kelly....it looks like they updated the info because
this 2015 Canada info sheet advises against use in ponds.

Canada Karmex


Zep, I use an insecticide that targets Japanese Beetle grubs in grassy areas that has Durion as a listed ingredient. I have to stay 50' away from the pond edge when applying it.

I actually stay 50' away from where the slope starts going to the pond, so it is closer to 60-75 feet from the waters edge.
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