Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Submerged weeping willow eradication.

When my 1.25 acre leveed (8-10' average with a few 18' holes) pond was filling over the past 2 years (we were in a drought) I saw 3 spots with willow trees sprouting in what would be 3-8' deep at full pool. I cut them flush with the ground and when they grew back they made more of a bush. I figured I would let them grow, they would die when they were submerged and they would make some great natural cover.

The pond is now nearly full, and a few months ago I cut the tops of all the little trees flush with the water surface (1' below full pool) and sprayed the tops with a herbicide. At the time I did not have any fish in the pond so I was not too concerned with that aspect of it. Last month I added 1000 CNBG and some of the tops of the willows are sprouting. I am wondering if it will be safe to spray the sprouts without risking a fish kill. There are 3 areas that I need to spray, the largest is maybe a 10' diameter, the next a 4', and the smallest 4 or 5 chutes. I will spray with a pump up sprayer from a bobcat boat (fiberglass pirogue).
This is what I have used in the past: http://www.dowagro.com/range/products/grazonPD.htm

It is a selective that targets broad leaf woody stem plants and works very well. My other choice that I have on hand is KillzAll (generic roundup). I mix it triple strength so I do not have to apply much and use half pint as a surfactant to help it stick.

With as much surface and water volume I have, should this be safe to apply?

No one?

With the Grazon PD, go to the label, open it and read the first paragraph of the Environmental Hazards. That should answer the question for that herbicide.

Do the same with the KillzAll and see what it says. Basically, the label is the law, so if it's not specifically recommended for aquatic use, no one will recommend it to be used in a way that isn't in accordance to the label.

I was not wanting someone to recommend it to be used if it was not accordance to the label, I was just giving an example of what I have used in the past (I have never used an aquatic herbicide). Since the portion of the tree that I would be applying to is above the water, not submerged, I was not sure if I needed an aquatic herbicide or not.

I guess I will just continue to clip the new chutes with the water surface until the plant drowns out.

Could you try glyphosate(roundup)? I have used it on some primrose I had and it didn't seem to hurt anything. If the trees are above the water line it seems like it would work. You can add a surfactant(i used a little dish soap)to help.

Sorry didn't see the killzall you mentioned. Yes I would use that.

Thanks jason,
Yesterday evening I ended up brushing on GrazonPD (with halfpint as an surfactant) directly to the leaf and stems because I know it is very effective on willow trees. This method was very time consuming but I know I got good coverage and the plants are already wilting as of this morning.
I did not want to use killzall in case any got into the water and to the shoreline it may kill my grass and cause erosion.