Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Duckweed control?

What do most of you use to control Duckweed? Anyone use Opti-amine?

What rates do you apply it for Duckweed?

Reward (active ingredient = diquat) will knock duckweed back very well. you need to be persistant with this herbicide to eradicate duckweed.

sonar or avast (active ingredient = floridone) will eradicate duckweed well. will require repeat treatments if the pond has flowing water.

Reward (active ingredient = diquat) will knock duckweed back very well. you need to be persistant with this herbicide to eradicate duckweed.

sonar or avast (active ingredient = floridone) will eradicate duckweed well. will require repeat treatments if the pond has flowing water.

I agree with Shan. I advise pondowners to hire me for the first treatment with Reward (and take notes), but do it themselves after the first application. You really have to stay on top of it to compeletely eradicate with Reward, but it can be done. The 3% that is not killed will quickly take back over if not retreated.

When using Sonar we will siphon or pump the lake down so the required ppb concentration is maintained for at least a month. It has worked 3 out of 4 times to control duckweed or even worse watermeal.

Todd: Never heard of OPTI-AMINE, but suspect it is a formulation of 2,4-D Amine - which is completely ineffective on duckweed, as is glyphosate (in case you should ask).

As for diquat (REWARD) or fluridone (SONAR): IF the pond is static or has very little potential for a flow-through event, and IF more than 50% coverage (assuming at least 1 to 2+ acre pond size), I'd lean toward using fluridone - especially if your application equipment is limited to a low-volume (hand-held) pump-up sprayer. On the other hand, IF your pond regularly experiences flow-throughs/over-flows, or has a high likelyhood of same with minimal rainfall, REWARD may be your only practical option. However, it is best to conduct REWARD treatments before the infestation reaches severe levels, since REWARD must contact all plants that are expected to secumb to the treatment (add CIDE-KICK to REWARD to increase it activity on the targeted plants). With REWARD, use the wind to your advantage. Treat (with the wind behind you) from a boat (pref a 12v ATV type sprayer) when the wind has the duckweed concentrated along a windward shoreline. Strive to contact as many of the duckweed plants as possible with the initial treatment (2 gal. REWARD per TREATED surface acre, diluted in enough water to allow thorough coverage). Conduct REWARD RE-treatments to surviving plants within 3 - 6 days. Otherwise initial-treatment survivors will quickly replace what plants were successfully controlled. Multiple duckweed re-treatments are the norm with REWARD, though each successive treatment should require much less product and time than the prior treatment. Use clean water ONLY when tank-mixing REWARD (muddy water ties up with diquiat very rapidly).
SONAR usually requires only one whole-lake treatment - dosing at 6-8 oz. per acre-foot (under conducive circumstances). Satisfactory control may last beyond one season, unless a reintroduction of the plant should happen, or a flow-through event occurs within the first 30 days after the treatment. SONAR requires this 30-day length of contact-time to impart its effect on susceptable plants. SONAR applications require only a bucket or pump-up sprayer. SONAR's dilution-ratio in the mix-tank is irrelevant - the proper dosage is based on amount of undiluted product in relation to the volume of water in the pond. Focus on achieving and maintaining the targeted concentration for at least 30-days (measure in parts per billion - ppb).
Unlike REWARD, fluridone is applied INTO the pond's water-colume as a properly-dosed pre-diluted solution (Do not apply fluridone solution on top of duckweed infestions. Direct sunlight quickly breaks down fluridone). Alternately, REWARD must be applied as a topical spray to all targeted plants.
Lots of "ifs" and requirements to consider in this thread. Any questions? Let me know.
KD

Thanks to all that responded.

Yes, the Opti-Amine is a 2,4-D. It was in an older "Green Book" os registered pesticides.

The duckweed is not out of control yet so the Reward should work fine.

I really like what I have read and heard about SONAR. It has a lot of good attributes but it seems pretty pricey.

One more quick question.

Can SONAR be used in mid summer on large amounts of Eurasian Milfoil without the fear of killing it too quickly and depleting the oxygen for bass?

SONAR's effect on suscepable species is anything but quick. However, when things do happen, they generally happen all at once. So yes, there could be concerns about a mid-summer fallout of EWM and the potential impact on DO by its decomposition.
However, possibly of greater concern is IF the SONAR would work very well with a mid-summer treatment (maybe not). SONAR's mode-of-action requires active and sustained growth from the targeted plant(s). If, by mid-summer, the EWM has topped-out and its growth rate has drastically declined, SONAR may provide less than optimal results. Best to treat in the spring when new growth is most active.

Thanks KM. This site is full of knowledge and knowledgable people. Once again, thanks to all that responded.

I really have to jump in here somewhere, I don't think this is all that much to deal with because it is one of the most common pests it has a cure.Sonar,if it is applied early. Get it knocked down.Touch up if you have to with Reward then forget it was there.Drain it down if you have excess flow. Throw in the Sonar and let it work.DOC

Doc: While most lake management professionals are familiar with various management options, methods and treatment techniques for nuisance aquatic species, I think it presumptuous to expect the same level of experience from those who visit this board for information and guidance regarding their questions. If I ask important questions to a medical doctor, I expect thorough answers and responses to “what-ifs” in a language that I can understand. “Throw in a few aspirin, knock ‘em down with some Jack, touch it up the next morning with a Bloody Mary and forget you were sick” isn’t going to satisfy my expectations. Maybe I’m wrong, but I suspect laymen pondowners may feel the same regarding their questions (which lie outside their fields of expertise). Just thought I’d jump in with that opinion. No offense intended.

NO offense here either but I tend to agree with Kelly. If you are going to run under the title of lakedoctor (which implies you are a true profesional) you shouldn't expense weed treatment advice casually and sound like a bar tender giving advice to a patron. Most of these herbicides are when in the jug "strong chemicals" and should not be treated lightly or casually. Casual handling and lack of respect and NOT closely following label instructions and application directions are ways how many persons produce poor results with use of these chemicals. Improper use is common with many casual users of herbicides which is why EPA is restricting their use and requiring an applicator license for use for more & more of the herbicides/persticides. Too much misuse.

Duckweed and water-meal are common weed problems as you say, but they are also environmental indicators of highly eutrophic conditions within the pond. When you have abundant duck weed, your pond is telling you, no it is screaming, that it is very fertile or over fertile and a fish kill is VERY likely due to the over enriched conditions. If you have frequent duck weed problems the pond owner should be very concerned with the conditions that causing it to grow very abundantly. The owners should be investigating, exploring and or doing management practices to reduce the conditions that are causing the duckweed problem. If those causative agents are not addressed the pond will continue in it's rapid downward spiral (pond succession). RIF one can reduce the causative agents, it will slow the aging process of the pond and maybe reduce or eliminate the duckweed problem plus reduce the chance for a fish kill. Often due to pond design or location, it is not feasable to reduce the causes of duckweed. Then one has to deal best they can with an aged pond.

You are right advice should not be handed out lightly but after reading the post that had already given the technical side of duckweed control I wanted to give a simple direct and to the point post that was easy to read and understand but maybe I should have put a warning about following label directions.But I thought you guys already had that covered. If a reader is after information on a certain subject they should read all the post and make their mind up how to go about solving their problem.If I caused any problems with this post I am sorry and will try not to let it happen again but in this time of the year I get in the hurry mode and don't slow down till winter my better half has to almost tie me to the chair to get me to take time out to eat supper thanks for letting me have it I need it once in awhile. DOC

LkDoc- Its your 'neck stretched out there' no one elses. The problem is that SOME people do not read all of the posts or only remember a select few; so one should always try to provide the best you can each time, just in case the reader remembers or selects only your advice.

Bill I do feel some of the people that come to this forum don't want a long drawn out post with alot of techical terms that only a pro can make any since out of. I received an email that explained that the post should be in plain talk and to the point. I don't want anybody that reads these posts to just go out and blindly do something just because I said to.I want to give people as much help as I can but in the end they are the ones that make the decision on their actions.I cannot be responsible for the results if I am not doing the hands on.I charge people good money just to show up and give them the 411 on any problem they throw at me about their lake or pond. But on here I get to sit here and relax and not worry about the business part and still get to help in some small way some of the readers.I like it when I get an email from somebody across the country just to say thanks and that's a pretty good pay off.Almost as good as getting a check .DOC

LkDoc - I'm sure you are right about what most readers here want in an answer. Posts do not have to be "long drawn out and full of technical terms" which are often features of my answers and often not the best approach for most.

Bob Lusk is a fine example of short and simple common language posts. One can use his style as an excellent example or mentor. He is not a frequent contributor when fish season keeps him on the road. But you can search his past posts for examples of what I am refering to. He does an excellent job in my opinion and I enjoy reading his style.

I think what KD an I were referring to was a style that 'we felt' maybe was too casual when dealing with herbicides which should always be considered serious stuff esp from a professional with training. Your style must have rubbbed our 'chemical feathers' the wrong way. However non-herbicide answers can be very casual and 'local'. I'm positive KD takes his herbicide stuff very very serious and I tend to agree with him. I think people in general take plant control & herbicide application way too casually and they need to be constantly reminded of the serious nature and consequences of hebicides and improper application. I think this is the point we were trying to make to you. I had several heated posts/discussions with KD before, I know where he is coming from. I had to learn not to take things here personal; they are not ment that way and intent and inflection are often very hard to convey with written words. As we said earlier no offense and don't take it personal. Everyone here is entitled to their opinion and as you know you are allowed to respond in most any manner at this forum. I guess that is what the rating system is all about, but not sure how effective it is.

Not to beat you up lakedoc. I catch myself making general statments here as well. but chemcial application advice needs a little more attention.

I have posted this before but I'll do it again. A few years ago I was spraying Reward on a very windy day. my sprayer is driven by a 5.5 Honda and puts out 9 GPM (max) the mist off the gun can be significant. I accidently caught a breath of that mist and it burned the hell out of the inside of my nose. I had nose bleeds for weeks. it took quite a bid of flushing (and all my drinking water) just to be able to drive home. I thank goodness I had enough sense to put my goggles on that day.

needless to say I look like the poster boy for chemical application saftey these days. be careful with these aquatic herbicides boys. wear your gloves, goggles or face shield, long sleeves, etc. you dont want it on you, I promise.

I get the point that you guys are trying to get across and your right.I don't take chances with herbicides.I always take the extra time to make safety my #1 priority.The thing that was missunderstood in my post was that I had read your post and believed that all the bases had been covered to the point a person not in this field would log off scratching his head and getting discouraged and confused.I think and believe that the chemicals that we in the field use everyday should be restricted.That is not the case in In.The only restricted chemical that we have or use is rotenone.Does that seem alittle crazy to anybody.I Don't want to step on anyones toes but I and I'm sure that anybody that is in this field has to be licensed and trained to apply these chemicals at least for hire.Is it in your or my best interest to post and explain the way to treat with these harmful chemicals.Ask yourself if you would hire anybody off the street give them a job without at least spending a good amount of time training them.Do you think that it is wise to post a treatment plan to someone that you have never even seen.That is alot of risk and I'll bet in some cases has had some really bad results.I just want to give a little different angle to these chemical treatment post maybe the best advise that we could give is the name of a pro in that persons area. DOC

lakedoc,

georgia is the same. anyone can buy herbicides for treating thier pond. I'm not sure if making everything restricted use is the answer not everyone can afford a consultant to treat their ponds.

I pick up several jobs a year from other "lake management" companies around here. they ususally hire high school kids to treat their ponds. the kids usually over apply copper or treat too much of the pond during the summer. their poor results are great for me, I like new work.

Doc: I can't stay on the sidelines any longer. I have to address some of your comments:
1) The OMISSION of information, rather than TOO MUCH information, produces more confusion and discouragement (esp. when undesired or catastrophic results occur due to an improper treatment).
2) Restricting chemical access (through licensing requirements) is comparably effective as our present narcotics laws (nuff said). Better educational efforts are crucial in both areas.
3) Ironically, rotenone is a naturally occuring substance (produced from roots of the cube tree). Only rotenone's aquatic-labeled formulations are "restricted-use"; more than likely due to past malicious uses (harvesting fish from a trespassed pond by the light of the moon???). The small-package formulations of rotenone are "general-use" insecticides for many types of ornamental garden pests.
4) At least in TX, commercial applicators of general-use herbicides to private ponds/lakes outside of incorporated city-limits do not require a applicators license. However, if I were hiring someone for such, I'd AT LEAST make certain that they were licensed (although that piece of paper no more guarantees a proper pesticide treatment than a drivers license guarantees proper driving habits).
5) In many situations, treatment "suggestions" may be accurately dispensed on boards such as this, but only IF a qualified person takes the time to ask the right questions BEFORE firing off a recommendation. Never shoot from the hip!
6) When properly and appropriately employed, these so-called "harmful chemicals" are very useful and environmentally compatible tools (BC: let us avoid another debate here. The thread is already too lengthy.)
My earlier posts may be too wordy; maybe not. But, if anyone reads my posts and is "confused" by what I've said, I guess I've either grossly failed OR they probably shouldn't attempt feeding themselves without supervision. KD

OK Kelly, Sign me up for Eating Only With A Spoon. My wife already says I need a bumper sticker saying "Doesn't Play Well With Others".

I'm curious.

Regarding # 4 your above post; I assume Rotenone is not a general use herbicide but in # 3 you mention its availability in small packages as a general use insecticide.

How small are the packages and in small lots are they affordable to someone who wanted to clobber a pond in the middle of the night or just bypass the cost of a commercial applicator?

Enjoyed meeting you in San Marcos and when the vegetation we discussed gets started in my forage pond, I will take you up on the offer of sending a picture for identification.

Dave

Hello Dave. Enjoyed visiting with you in San Marcos as well. Besides the legally improper labeling issue, small-packaged "Garden-Labeled" rotenone isn't what I'd call an economical option for such covert purposes. One website that I found lists a 12 oz. container of Rotenone 5% Powder at a $15.93/lb. equivalency. Fish-control treatments generally require about 10 lbs. of 5% rotenone powder per acre-foot. Based on this info, it would cost approx $637 to effectively treat a small 1-acre pond with a 4' avg depth. Not exactly what I'd call cheap - especially considering the very real risk of being shot, labeling-laws and the amount of time and manual labor required; not to mention that you can legally buy a lot of fish at the market with that kind of money. However, I'm pretty sure that spoons are the typical eating utensil in prison. For one's own legal purposes, it would be well worthwhile to obtain the appropriate license. Otherwise, hire the job to a professional. It is the private-market's circumvention of pesticide label-laws that will quickly bring an end to private pesticide availability - ie. chlordane, Dursban, etc. KD

Looks like I ruffled your feathers alittle bit KD.I think that your post are packed full of all the info. that is needed to get somebody on the right track of solving their problems and as far as I have seen you have been right on the money with your advise.The one thing that I haven't seen in the post is some of the important advise that is a big part of making the right choise when treating a pond.Like I said saftey is the #1 priority.Shan was the only one that memioned the subject the fact that I might sound like a bartender when I shot my post from the hip was ment to prove a point.If there is advise handed out and it has health risk to a person or persons then it should always be included.The fact that nobody menioned that sonar should not be applied within a quarter mile from a potable water supply is leaving out alot of information about this product.There is this type of info with every chemical that should be included before a reader goes buys it and finds that they should not use it.The chance of somebody taking some advise from a post and using it sucessfully is great but it won't be if they end up sick or worse.Just something I just had to post.Gotta go get my drivers license renewed. DOC

A few years ago I was applying some granular STUFF
(not sure that remember the name)to my pond and I didn't have good enough eye protection. My house is less than 100 yards away. I ran to the house
got in the shower, held my eyes open under water for 20 minutes. The pain was still more than I could bear at this point I was screaming. My wife took me to the emergency room. I was afraid that I would be blind for life. Luckily the damage was not permanent but it could have been.
This is just my two cents worth on the fact that
you CANNOT BE TO CAREFUL when using chemicals.

Sorry to hear about your accident David.Did you have any training is this field before your accident?If not where did you get the advise on how to use this product.If you had it to do over would you be more interested in finding out more saftey tips?Would you hire a pro instead?If something like that happens to you It makes you think twice about the stuff you could have loss if things would have went the other way.I'm glad your ok and things worked out. DOC

Doc: Have you ever considered a political office? I'm smiling! and couldn't resist.....
No, my feathers are fine. It is Hollywood actors and actresses, who think they are more enlightened than us "common citizens", who ruffle my feathers.

David: Copper sulfate, aka "Blue Stone" -probably the "granular stuff" that you were using- is extremely caustic, with long-term or permanent damage very likely if it gets in your eyes. Goggles are too cheap not to use when applying products, particularly granular versions. Thanks for posting your experience. You may have saved someone from a similar agony.