Pond weeds
 

Can you spray weeds and water lillys in a pond and not hurt fish in the pond?

Yes, but I don't know the name of it. Had a guy come by our neighborhood and spray all the ponds for cat tails, etc. Fish, turtles, etc. were ok.

There are a species of fish that eats pond vegetation. I forget the name though...sorry!

Glyphosate may be the stuff, but reseach it further.

Texted a friend!! The fish is called a Triploid Grass Carp. Being triploid means they are sterile. Are very effective.

Didn't know they were called Triploid...learned something new! Yep, sterile grass carp is what ya want (just make SURE they are sterile)! I need to source about half-dozen or so for one of my ponds as my old grass carp have died in the last year or so. They were at least 10 years old and had grown to probably 3' in length over time. No way, no how would I use chemicals in my spring fed pond...but that's just me...YMMV.

Depends on what kind of weeds - for example, they don't eat water lettuce.

Best may be to check with your local ag extension office for info or a reference to info

Bill is right - Glyphosate is the active ingredient in the product "Rodeo" used for aquatic weed control.

Now keep in mind, this is the same active ingredient used in "Roundup" - used for weed control in landscapes.

The difference is a legal one - one labeled for aquatics one for non-aquatics.

Those who do this commercially must stay in compliance. I don't see why a homeowner couldn't use Roundup in an aquatic application though as long as they follow the "Rodeo" label as the active ingredient is the same.

http://www.midwestaquacare.com/product-labels/rodeo_label.pdf

Keep in mind....there is a % of Glyphosate listed (53.8% in "Rodeo") and since the patent protection ran out on Glyphosate it has been produced in various % offerings from both Monsanto as well as other companies such as Ortho, and several others.

Always check the label - specifically the list of active ingredients on a product before purchasing.

Also the use of blue dye will help control algae and other pond weeds so keep that in mind - these dye products are available from several companies...

Roundup is rumoured to be linked to numerous environmental after effects...as in the new DDT.
I'd go the natural route if possible.

I'm certainly no pond expert, but have been told that the "real" reason for uncontrolled weed/algae growth is the the pond is too shallow...needs to be approx 6' deep or so. If sunlight can reach the bottom, growth will thrive...I suspect the "blue dye" is effective thusly. I'd try natural, "organic" appoaches first (grass carp, etc.) that provide an "ongoing, natural balance" for control rather than chemicals, but that's just the way I choose to go. Contacting your county agr. agency, or a university's agr. dept. is an excellent idea (NC State is a great source for my area)....good luck! I do like my ponds :D

Grass carp - $14.00 each or more and will control weed growth (not algae) for 6 to 8 years. They eat Bladderwort Naiads, Chara Parrotfeather (Myriophyllum), Coontail (Ceratophyllum), Pondweeds (Potamogeton), Fanwort, Widgeongrass, Hydrilla, Spike rush. Also, they post no effect upon total standing crop, shad biomass, numbers of catchable largemouth bass, sunfish, and crappie, or numbers of young-of-the-year sunfish and bass. The plant removal by grass carp did appear to improve the condition factor of largemouth bass, bluegill, and redear sunfish.

I say stock the pond with these babies and sit back...

Devil's lake in Lincoln City, Oregon was choked with weeds. They went the sterile carp route. It seems to have worked.

As an aside, this lake is known as the headwaters of the world's shortest river.

Timely topic. I have just started a pond build. I have been longing for a Koi pond for many years. Last weekend we dug out more than 80 cubic meter including the filter pit.

it (aka, RoundUp) can be used in aquaria so that would be my 2nd choice; they add so-called "inert" ingredients to it, some of them may be the source of the rumors as inert does NOT mean it is really inert

1st choice - call the Agr. Extension Office for your county - your tax $$ can be put to work for you and you might just have some horrible exotic alien weed infestation that they should know about - might also come out and do the dirty work for you

if the pond is too shallow, or you fertilize the lawn or fields around it then you are hosed - search on "eutrophication"

"

Though I have no issues with fertilizers, etc., one of my ponds is definitely a bit too shallow on one end (3' deepening to 10') which contributes to my issues. A few grass carp certainly mitigate the "problem" though, and have done so for years ;)

Use Rodeo or aquatic 2,4,D. Spray no more than 1/3 of the pond at a time. Too much die-off will cause oxygen problems and kill your fish. Use only an aquatic approved herbicide for your pond. The legal aspects of not doing so could get really sticky in a hurry if you get my drift.

Thanks for the replys. So it is safe to use round up? On the carp willl they eat the existing fish? This pond is loaded with Catfish, Bass and brim. Standing on the side of the pond, feeding them, I saw a bass that was about 5 pounds. Don't want to put in another fish and kill what "hasn't been caught yet"

how safe is safe is the real question - call the Ag. Ext. people for the best advice they are likely on the LSU campus

Grass carp are vegatarians as far as I know...regardless, they won't have a negative impact on a pond full of bass, crappie, and brim. Just make sure they are STERILE, or you will eventually have a pond full of carp...probably more of a nuisance than weeds :D. That's why they cost $10+ each....the sterile verification process. I saw a sign for "grass carp" at a garden center last year, but they weren't sterile...you certainly don't want those. Since you're in BR...I agree with Randy...contact the folks at LSU and see what they have to say....good luck!

We used copper sulfate in a burlap bag drug quickly through pond. Can usually be found at swimming pool store. Cheap, quick and effective. No harm to trout from what I could discern.

But here are the cons if one acts like a complete fool....

Copper sulfate - negative effects on lakes and ponds › Aquatic Biologists

Note for cattails.

"Application timing is critical for cattail control and differs between diquat and glyphosate products. The contact herbicide diquat can be applied any time the cattails are green and actively growing. Most owners using diquat products apply in the summer. Glyphosate products have a narrower window for optimum results. These products should be applied just after the seed head has formed. Energy reserves are at their lowest in the roots and the plant begins to store food in the roots in anticipation of next year�s growth. This food is produced in the leaves and transported to the roots. The application of glyphosate at this time results in its transport to the roots as well, thereby killing the root system. "

Cattail Management

This is a pic I posted recently of my largest pond, and it's been a healthy eco-system for longer than I've been alive. Spring fed (output is equilavent to a couple of water hoses on full blast) and full of life. Unfortunately, someone caught (and hopefully ate, since they were probably migrant workers) the bigger bass (10 lbs +), quite a few years ago. There is simply no way I would introduce chemicals...YMMV. When this pic was taken, the overflow pipes were clogged...unclogged, and now most of that crap on top is gone (flushed through the overflow pipes). This is my little slice of "heaven" :D http://forums.pelicanparts.com/uploa...1367494454.jpg

You have some good shade and wind protection with that tree line. Some water lilies might help control your algae issue though. An algae die off, which happens over night, can deplete the pond of oxygen. Your spring might mitigate the damage of an algae die off.

Algae die offs can literary kill the fish.

My first rule-of-thumb is "do no harm"...hence I tread lightly on anything that might upset a balance that's been intact for decades. The algae isn't really an issue for me, though that pic shows it at it's worst...the real weed growth is underwater. I've seen more than my share of "fish kills" due to oxygen issues in other bodies of water over the years. I just don't take that risk...

If you don't like chemicals (many chemicals in there already by the way) put an aerator in the middle to supply more 02.

Out of curiosity, why do you think my pond needs more O2? It's as healthy as can be imo...just needs a few grass carp :D. Probably aren't any significant amount of chemicals in there either, other than those found in the aquifer...no fertilizer run-offs, etc. reach this one. I would drink from that spring if the pond was drained. Sorry for the hijack...

ps: Judging from the arrowheads found in the surrounding area (many dating back 4-6000 years)...I suspect the Native Americans did too ;)

Walk across the bottom at the shallow end. Smell anything? The algae and bacteria strip away the 02 leaving smelly hydrogen, sulfides, and nitrates/nitrites (chemicals).

An aerator would cut down on the (from the pic I'm guessing) floating algae. You can even find solar powered ones.

Good water is all about balancing. Man can either make it better or worse. Almost all ponds can be improved.

Thanks Manbridge! I must admit it's probably been 40 years since I've walked in the shallow end, so I have no firsthand experience as of late :). I've never even caught the faintest whif of what you describe (and I am familiar with the smell) when the dogs get in an stir things up though. Not arguing with ya...I might actually accidently learn something! BTW, I dare say that 75% of that floating algae is now gone...it accumulated when the overflow pipes were clogged. Wind shifted in the proper direction, pushed it towards the yonder end and algae was shooting through the overflow pipes like crazy for a few days as the water level dropped down about 6 inches to it's normal level.

Carl Spackler: This place got a pool?

Ty Webb: Pool and a pond... Pond be good for you.

healthy is hard to judge sometimes

ponds go thru a natural process of "aging" or succession - a clear alpine lake would be at one end (little or no life) and a swamp near the other end; eventually, the all ponds fill in with debris and become land

I agree with manbridge tho - check the shallows, even snorkel in the deep end and see what is going on at the bottom sediments - you can maintain the pond more or less where you want it by careful mgmt. and it will change little over a few decades

also, chemicals and fertilizer can travel 100 yards easily


if you get really, really into this you could find a textbook on limnology and read it, then dial in for your area and soil type

Thanks Randy! Sorry about hijacking this thread :)