I have a 1 acre pond and is infested with a sumerged grass. We have been putting in Crystal Blue Pond dye in it. We rake about every time we go over to pond but grows back. We only have 3 grass carp two has got large in size so only one grass carp is doing the job I guss. We are thinking about stocking some more grass carp now. I was just wondering what could I do to kill this grass. We think it is widgeon grass but we are unsure. This pond has never been fertlized would that help or herbicide.
,Thanks

Hey BG Fever - I love your handle...welcome to the forum.

Can you provide a picture of the vegetation for us? Experts can then ID for you and provide management tips.

Widgeon grass is generally considered a beneficial plant...in moderation.

Welcome again - glad you found us!

http://www.bigbluegill.com/photo/a-type-of-grass-in-my-pond. and here is another picture. http://www.bigbluegill.com/photo/another-grass-in-pond?context=user

These pictures are grass from the pond. The first picture is on top of the water and the second picture came of the bottom of the pond. We bought a bag of copper sulfate but we don't know what is the best to control this grass. Does the pond need to be fertlized or do we need to put in another type of herbcide.
,Thanks

I can't see the pondweed well enough to identify it, but I do know the copper sulfate will not do much to kill the weed. Copper products are for various types of algae and not for killing leafy plants.

So what would you recommend putting into ponds to kill pondweed.

See if this is it.

http://aquaplant.tamu.edu/database/submerged_plants/baby_pondweed.htm

Mgt -

http://aquaplant.tamu.edu/database/submerged_plants/baby_pondweed_mgmt.htm

http://www.bigbluegill.com/photo/more-aquatic-weeds?context=user

This is another picture of this weed.

BGF - I'm fairly certain that the surface-growth is Variable-Leaf Pondweed and the submerged grass is southern naiad (Najas guadalupensis). If not Najas, the submerged mass could actually be a portion of the Variable-leaf Pondweed. Do the "two" plants appear to be connected (the same plant)?
The "best method" for controlling either/both (in August) isn't an easy call.
The control-method that poses the least amount of risk to your fish is manual removal. But, this will entail repetative efforts.
As for herbicides, AQUATHOL K might be the option that poses the least amount of risk - but low dissolved oxygen (DO) could still become an issue if the treatment it conducted too aggressively. On the other hand, poor weed-control results could result from an inadequate treatment approach.
Many variables come into play when formulating the appropriate level of treatment. Your pond's size, depth, water-temp, the presence of an effective aeration system, water-exchange, weed's population-level (% of coverage), etc, etc. If you want to elaborate on these variables, we might be able to give you better guidance.
It is far better to tackle aquatic "weed" problems before Aug - and before the plants become overpopulated.

What can I do next year to stop this weeds from growing. Do I need to put AQUATHOL K in the spring of next year because the weeds are already seeded for next year. Another Question would grass carp eat these weeds.