I may have a pond full of picky eaters. I think that I have seen evidence of the milfoil being eaten by the GC. I could be wrong but I would be okay with them clearing out the milfoil. Speaking of milfoil, does this stuff just float around without be rooted into the pond. I get large amounts of it pushed against the downward wind side of the pond after a strong wind event. I rake it out and after the next wind storm another pile has shown up. Also, what happens to the milfoil in the winter months?
I think the GC need to be larger sized such as 24"-30" to readily eat milfoil. The stems of especially older plants are a little firmer and maybe not as easy to eat as the soft leaves and new sprouts. Stems are considered stout and leaves fairly soft.. It normally grows rooted to the bottom. The flowers (Jun-Aug depending on location) above the surface as pinkish spikes with tiny yellow flowers produce seeds but it mainly spreads by fragmentation and rhizome growth. After the fall flowering the plants usually die back to the root crowns which regrow in spring. This die back could be why you are now seeing large amounts wind rowed after wind events. When GC start eating Milfoil they do not get all the material in their mouth thus numerous plants escape and float. In mid season when you are seeing floating stems this is a sign the GC are working on it. Don't expect good control of it until your GC are bigger individuals.
