Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants How to control widgeon grass?

I live in central Michigan. My pond is two acres in size and is spring fed. It is 19 feet at its deepest and averages about 12 feet. It is about 13 yrs old and has extremely clear water. I have what I believe to be large patches of widgeon grass growing in it. It has a string like look and feel to it. The odd part is that it grows in deepts of up to 8 feet.
It now is growing by my dock and swimming area. What chemical to I use to control this weed? How is the chemical applied? The widgeon grass grows to just beneath the surface so how do I apply something to kill it.
Any help would be greatly appreciated.
P.S.
I am almost certain that it is widgon grass.
Thank you

Can you take a picture of it?

Hello
Thanks for the reply. The ice just left the pond yesterday.All of the widgeon grass died last winter. I did rake a very large amount of the weed out of the pond last summer. When on shore it looks just like green string. I did do a fair amount of research on the web and it looks just like the pictures and descriptions of widgeon grass. I thought that I read somewhere that widgeon grass only grows to a length of about three feet. This weed in my pond grows to eight feet plus. The water in my pond is extremely clear most of the year. I can usually see the bottom at depths of 8-14 feet.
How do you apply herbicide to a weed that grows from the bottom to just below the surface? Which herbicide would be best to apply? Any advice would be greatly appreciated.

I have experienced WG at 4-5 ft but not 8 ft plus.If it is WG and when you get your temps to 60-65 plus a chelated copper and diquat and a surfactant work well on it. We inject by simply submerging wand and streaming it into the area of growth.I realize you have researched this but get another positive ID to be sure you are not treating a look a like. Any closeup pics from last year that you can post?

Thank you for your reply. No, unfortuately I don't have any
pics of the weed in my pond. Every summer and winter the local
sheriff department's dive team uses my pond for practice dives.
During the one last summer one of the divers surfaced near my
dock and was litterly covered in the long grassy, stringy looking weed. Pictures were taken of the diver becaused it looked so funny. I will try to obtain a picture and maybe that
will help identify the weed.
If it is widgeon grass, you say you submerge the sprayer wand
below the surface of the water and the liquid disperses to the
weed and kills it. I was hoping that there might be a granular
herbicide that I could just disperse on the surface over the weed beds. How effective is the spraying under water to kill the weeds? How often does this have to be repeated? Is this very threatening for the fish that are in the pond?
Thank you for your help.

Could it be a type of eel grass?

Hello
For the last few years I have been watching the spread of this
weed. I have compared it very closely to the pics and decriptiion of widgeon grass. Everything fits, except that it
grow to such depths in my pond. It is not rooted very solidly to the bottom and floats to the surface when dislodged. It grow very densely and looks like a large green pile of long string when piled on shore. Some of it was alrigt, but now it
is getting more and more invasive - growing around my dock and
swiming area.
Thanks again for all of the replies

Take a picture when you can. Herbicides should be applied when it's actively growing, which usually means water temps above 60°F.

Scott, I have searched the threads, and haven't found what I'm looking for, so here goes.

As bad as I hate to, I'm gonna have to spray Naiad and Coontail this Spring, as they are already growing aggressively. Conceptually, I have no problem spraying, and do so with emergents as needed. It's just our annual water table drop usually corrects any problems.

So, do you guys just use standard wands under the water to spray the individual weeds, or is there a better method? Also, is a surfactant still needed?

EDIT by me: The method has been addressed above, but are there any tricks, or gotchas?

I use a gas powered ECHO back sprayer for small applications. I set the nozzle to mist and can lower it to 5-6 ft and easily see the coverage.I do not dilute the Cutrine 8-9 parts to 1 as at 2-3 to one it is heavier this way and stays in the target area.I believe Cutrine is in the 10-11 lb per gallon range and water 8.34 lb per gallon.I always use a MSO or a general non ionic surfactant for under water applications. With it costing just pennies per tank.My understanding is that the initial penetration and adhesion through and on leaf tissue is better with it than without it.My understanding also came from the manufacture selling it.What chemistry are you considering?Have you looked into Aquathol Super K granular to see if it fits?

Thanks for the advice Ted, yes I have looked at the granulars, but I have the liquid Aquathol Super K already.

Thanks again, I'll try it this week.