Hi All -

I'm in need cost effective solution to remove vegetation from two ponds used for dog training. I am thinking about using grass carp to control weeds, but I am unsure if vegetation can be controlled effectively by grass carp. The two ponds are 1 & 0.6 acres. I have included several pictures to show vegetation. Any and all suggestions would be very helpful.

I doubt Grass Carp would control that. I'd recommend getting something like Rodeo to spray on it. Quick Google search shows you can get a 2.5 gallon container for $100. Add a surfactant to the spray mix and you would be good to go.

Chris - Why do you think grass carp would have trouble controlling? There appears to be heavy vegetation under the surface plants. Would Rodeo take care of the sub-surface plants as well? Any ideas on increasing length of time in between spraying applications?

From the pictures you have I couldn't tell that there were subsurface weeds. GC stocked in high enough density will control most vegetation but I don't think they will control the floating plant because of its structure. That looks like Watershield to me and it has a thicker stem that would be hard for the GC to eat. According the www.aquaplant.tamu.edu GC will not control watershield.

Depends on what species you have if Rodeo will control it. Go grab a handful and post some pictures. 2-3 weeks between sprayings is adequate.

Chris is correct. GCarp may eat the submerged weeds but not likely the floating weeds of water shield and others like water lilies. Post some pictures of the submerged weeds to get identifications.
Read through this for making good pictures of pond weeds.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=371748#Post371748

Thanks everyone. I'll try and get some better quality pictures.

Are there any chemicals on the market that will wipe out all vegetation without having to identify all plant species? Once vegetation is controlled, would adding dye to the ponds help reduce vegetation comeback? What could give me the longest time period between needing treatments? I know nothing about pond maintenance so please forgive me if these are all questions that hinge on knowing the plant species.

Also, the floating plants posted in the pictures were coated with slime. After reading the description for water shield, it appears that is correct.

The broadest spectrum herbacide that I know of (if you don't have water inflow and outflow in the pond) is Fluridone.

(Sonar A.S., Whitecap, etc.)

But you need to use it at the dosage rate of 90 PPB for it to be effective on the majority of vascular plants.

Agree with the systemic herbicide approach of Fluridone for more permanent results and far less labor/hassle of spraying the entire BOW.

I have used Aquathol Super K for years and it does a good job on both submerged and weeds with surface leaves and is not harmful to fish. It is expensive tho - last 10 gallon pail was $250 - but it does go a long ways. I have never had much luck spraying Rodeo on weeds with surface leaves. See my new post under Corrective Stocking - I planted grass carp and I now have NO weeds of any kind in the pond. I have even seen the GC pulling on the cattails trying to rip them loose and on one occasion saw one dragging a piece of cattail around the pond.

You might also Google - Grass carp Devils Lake Oregon. They had a problem with what appears to be weeds with surface leaves like yours and apparently the grass carp ate those and anything else they could get their lips around !!

The pond owner has previously sprayed the pond with Kraken aquatic herbicide. From what I heard, the surface vegetation (primarly watershield) died off but then returned. Would an application Rodeo prevent watershield from returning?

http://www.sepro.com/default.php?page=renovate

Has the same active ingredient as Kraken.

Rodeo is a glyphosate based herbicide. Systemic herbicides are absorbed and move within the plant to the site of action. Systemic herbicides tend to act more slowly than contact herbicides. An aquatically registered surfactant (see the label) will have to be added to the glyphosate solution for good results.

If Rodeo applied correctly, and it is translocated to all the roots, then yes, it will kill all the Watershield. But, any seeds that germinate will have to be killed the same way before they reach maturity and spread more seeds.

So is Rodeo superior to Kraken because it will translocate to the roots? Or are they same product and will produce similar results if applied correctly?

Give a person a fish and they will eat for a day. Teach a person to fish and you will feed them for life.

In your picture veg1, it looks like Watershield. Go here, and see what they say about what products work on it, and how effective they are:
http://aquaplant.tamu.edu/management-options/water-shield/ You might want to bookmark that site because they have a LOT of plants listed, and it is a very good site to ID plants and it also tells you what chemicals work on them and how effective they are.

Now look at the active ingredient in Renovate (same as Kraken)
http://www.sepro.com/default.php?page=renovate

and Rodeo
http://www.dowagro.com/vm/products/rodeo.htm

You might also want to look at the active ingredient in Navigate:
http://www.aces.edu/dept/fisheries/rec_fishing/documents/navigate_label.pdf

With that said, if you were called to treat that weed problem in a clients pond, what one would you use?

Thanks for the links. I've actually already taken a look at the first link before. The vegetation in the picutres is watershield. All three herbicides listed above are systemic. Based on the ranking system provided in the first link, I'd say Renovate would be best application.

Wish you would tell my RES that. They did not get the message.

I noticed the other day that a good portion of the watershield has begun to die off. I do not believe any herbicide was used (multiple people have access to the property). This got me thinking about weather patterns and if watershield dies off during the winter months. I researched and found:

Annual Cycle: Watershield is an aquatic perennial that propagates by creeping rhizomes, seeds, and winter buds (or turions). Flowers are produced in early to mid-summer. Seeds and winter buds are produced in the late summer, and settle to the bottom as the plants decay. Rhizomes, seeds and winter buds sprout new growth as the water begins to warm in the spring.

What I found was not clear whether watershield will die off during the winter. I did find it interesting about the winter buds that are produced. Is there any way to kill the winter buds on the bottom and will watershield die back during the winter? I'm looking to try and control the watershield and minimize a complete over growth this spring.

Any herbacide should be applied during periods of plant growth, not on dormant plants.

The only thing that I know that's contrary to that is topical application or basal injection of specific herbicides to woody plants (i.e. trees or bushes). So, that's not applicable to aquatic plants.