Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants What is it?

I have weeds in my lake, I assume they are a type of water lilly, but I am not sure. All of the water lillies I have known have much larger leaves. They have oval leaves , about 2-3 inches wide that float on the surface. The underside of the leaf is a dark red color, and the stem is red with an odd clear coating. They spread very quickly. I don't mind a few for cover but they are going to take over quickly if something isn't done. I was hoping there was something I could do to control them without herbacide(grass carp, talapia etc.)

I think yor plant is water primrose.. check this link out
http://www.pondboss.com/ubb/ultimatebb.php?ubb=get_topic;f=13;t=000001

K,,did you follow the link.. Is that what you have?? Please let us know :rolleyes:

I don't think that is what I have. I pulled a google search and all of the pics I saw listed for water primrose looked entirely different from what I have. Whatever I have grows very much like water lillies. Oval leaves that float flat on the surface of the water. There have been no blooms as of yet. It spreads by an underwater stem rooted to the bottom of the lake.

Thanks, the link gave ma a place to start. I kept searching and found what it is. It is water shield. I would still like a few tips on how to control it. I don't like using chemicals.

treating some today. difficult without chemicals, grass carp do not like it. If you decide to try chemical, most economical is aquatic glyphosate 2% solution, and 1% of 2,4-d liquid and surfactant. It may requie 2-3 appliaitons but will slowly reduce abundance. We used to use and recommend 2,4-D granular (navigate, aquakleen) but has gooten so expensive.

Sounds like watershield. The coating on the stems is a clue. A jelly like substance develops as the plant grows; this unfortunately makes the plant more resilient to contact herbicides. your description of the leaf shape and the red color to the underside fit watershield. Catch it as fast as you can. It spreads similarly to floating heart (Nymphoides peltata) by sending out runners on the bottom that develop quickly into new plants. Greg Grimes has a great recommendation. Hit it both ways, systemic (glyphosate) and contact (2,4-D).

Try laying sheets of black plastic weighted in place over your worst areas for about 2 months. The lack of sunlight should kill off the plants.

I was wondering if removing it manually would work or if it would cause it to spread to other areas? How deep o fwater will it grow in? It seems to only like the shallow areas, at least one saving grace, most of the lake is pretty deep, up to 25 feet in some areas. I will try the tarps, guess it will kill without encouraging spreading. Thanks to everyone for the info.