I have two species of aquatic vegetation that I need some assistance with. I have introduced grass carp into the pond over the last two years and I do not feel that they are having any sort of impact on the vegetation problems that I have. I am not interested in completely removing all of the vegetation as I understand that it provides cover for the forage fish.
My questions are:
What are the names of the vegetation?
Do the grass carp eat any of this vegetation?
What would be the best method to combat this vegetation in a few areas?
Triploid Grass Carp will eat Plant #2, to me it looks like Eurasian Water Milfoil. You can spot treat it with Reward, Aquathol Super K, Navigate and other chemicals. You can kill all of it in the pond with a low dose of Sonar AS, but you would be better off doing that route in early Spring when water temps are 60°F-65°F and you have no water flowing through the pond for 30-45 days. You CANNOT spot treat with Sonar AS, it's a "do the whole pond at once or don't do it at all with that chemical".
Plant #1 to me looks like Dollar Bonnet or Water Shield. It can be controlled in areas by spot treating it with Habitat, Arsenal or Navigate, Weedar 64.
Read the label on the bottles and follow the application directions. Follow the mixing directions closely, more is not better.
The thing with Triploid Grass Carp is you cannot tell them to eat the weeds in this area and not eat the weeds in that area over there.....
Kudos to you for posting good clear pictures to allow us to ID the plants.
I also believe that Plant #2 is Milfoil but wanted to get some professional opinions to validate. I think that the Grass Carp are eating it (or I'm convincing myself that they are) as I see stems with little of no foliage on them floating around the pond. I have about a 2 to 3 hundred foot section of shoreline that I would like to cleanup for ease of fishing as well as aesthetics. Can I treat with any of the chemicals at this point of the season or do I need to wait until cooler water temps? As far as the water flowing through the pond, I have a constant flow of water through the pond 365 days of the year.
Do you feel that the carp will eventually get the milfoil under control or do I need to consider treating it?
FYI: The pond is roughly 5 acres and I put in 40 Grass Carp in 2019 and 50 more in 2020.
If they aren't controlling it to your liking now, they may not be able to. They won't work on the Water Shield until there isn't much left in the pond for them to eat.
How far out from the shoreline will you be treating? What's your water temperature?
I have added a picture to my original post (Plant 3) that may show that the Grass Carp are eating the milfoil. Tell me what your thoughts are concerning this. The picture contains pieces of the same stem where is appears that the foliage has been removed. I have lots of milfoil that floats to the overflow and stops up my screen. Some looks like the stem on the right but much more of it looks like the stem on the left.
As far as the area I plan on treating. The shoreline area would be 20' to 30' wide and about 200' long. I do not have a water temperature. How would you recommend I take one?
It could be them. I've noticed a lot of floating vegetation in ponds with TGC where there is plenty of plants for them to eat, I guess if a piece slips out of their mouth they just grab another instead of chasing it down.
