I too have curly leaf pondweed that I have dealt with for at last round 10-12 years. When the curly leaf at about 2ft to 3 ft tall was abundant during winter ice cover, I had a real hard time catching yellow perch(YP). I am convinced the perch were down in the weeds and did not see or now there was food and bait present. I had to fish above the weed tops and perch were not holding at that depth. When they did find the bait catching fish was easy. I have a lot more YP per acre in my pond than you have trout. I think trout will be much more active in 39F water compared to YP.
I started killing the curly leaf (sonar 10-12ppb) in fall and sometimes AGAIN in the spring when water temps were around 48F-55F. Fall treatment give me a pretty clean bottom during winter. Diquat is another good herbicide for curly leaf. Diquat kills the curly leaf fast and the chemical decomposes fast in a week or two. I have used Sonar for around 6 years now. This pretty well reduced the curly leaf to a rare, short 6"-10" plant on the pond bottom in winter with sparse plants during spring - summer. I did not treat this fall 2020 and since ice has only been 2" thick as of Feb 02, I have not used the camera to check for curly leaf growth on the bottom. Ice is now thick enough for the ice shanty so I will check for plant growth and try to feed perch tomorrow. I have most of the pellets softened and rolled into 1/2" dia pellets. When I feed the pellets the minnows/shiners find the food first and quickly. This attracts the perch.
Time will tell the rest of the story.
Last edited by Bill Cody; 02/03/21 08:28 PM.