Pond Boss Forums AQUATIC VEGETATION Identifying plants Plant ID help Please!

Guys,

I would appreciate some plant ID help for these 2 plants.
And will grass carp control these plants???????

Plant 1 the leaves are around 2.5 to 3 inches long. Is this floating leaf pond weed (Potamogeton natans)? If not, any thoughts?





Plant 2 is growing in dense bunches. Is this small pond weed (Potamogeton pusillus)? If not, any thoughts?

First one looks like American Pondweed or Watershield. Can't tell which one. The underside of Watershield will have a slimy covering.

Don't know the bottom one.

Top one looks like American Pondweed or Illinois Pondweed. I can't really tell the difference, but I'm with Chris on the American ID.

Not sure on bottom, maybe Small Pondweed. Good news is I think any cultivars mentioned above are beneficial, if managed, and shouldn't illicit concern.

What made me guess Floating leaf instead of American for the first plant is the "heart" shape where the leaves attach to the stem but I'm definitely not an expert! I only have the one small area shown in the photo.

The second plant is a bigger concern as it is showing up everywhere around the pond. Hopefully, somebody will recognize it and give it a positive ID.

I'm hoping grass carp can help?? If yes, the problem I have is I don't have a source for the carp until October.

Specific ID really isn't that critical, as both can be controlled by the same chemical.

Don't look for TGC to be a magic immediate bullet - I typically don't start to see them working much until a year after stocking.

Yep. I agree on that first plant cause it is very non-invasive, so far anyway. I could just pull it up tomorrow and it's gone. The second plant has me concerned some. It is spreading fast. I would really like to know what it is and if TGC will control it. I don't mind if it takes a year or two for the carp to get it under control.

They will, it all depends on the plant density and how many fish are stocked. If you want faster control, Aquathol K.

I'm fairly certain that the floating-leaf plant is long-leaf pondweed ( P. nodosus), which has a more rounded leaf-tip compared to Illinois pondweed.
As already referenced, the submersed weed is most likely P. pussillus.
I agree with Esshup that grass carp are an option for slow, but long-term control; while Aquathol K or Super K can provide quicker seasonal-relief.

Thanks for all the inputs guys!

I've never used Aquathol. Is there a way to spot treat with it? I don't want to wipe out either species, just manage them. Also, would getting one of those weed rakes and doing some mechanical removal of the small leaf weed be a bad idea?

I do think I will stock a few grass carp this fall. How many should I get for a .4 acre pond? They will need to be at least 8 inch fish to avoid predation.

A question on Aquathol. Will it harm hardy lilies, duck potato, water arum, lizard tail, creeping rush, bulrush and eel grass?

http://www.aquaticbiologists.com/media/51264/aquathol%20label%202015.pdf

Are those plants listed on the label?

Yes, I read the label earlier which is why I asked the question. The label only lists vegetation it is recommended to control. It does not list vegetation that it is safe for use around. I suspect it will kill some species of vegetation not listed on the label but maybe not.

To ask the question another way... Does anybody have experience applying Aquathol in ponds containing hardy lilies, duck potato, water arum, lizard tail, creeping rush, bulrush or eel grass? Did the Aquathol harm them?

Bill, I've learned to never say never when responding to such questions,
since Murphy's Law and Mother Nature have proven me wrong on a few occasions.
I would suggest that you PM the UPI rep (mfgr of Aquathol) with your question > JSlade (Member #9310)

Thanks Kelly. Will do.

I've seen one grass carp completely denude a 0.25 ac pond that had lots of P. pusillus and two large patches of water lilies. In 0.4 ac add only one GC then evaluate after 3-4 yrs before adding 2nd GC. You want the GC to assist in trimming plants not eliminate them. You want to remove 1/3 and leave at least 1/3 as habitat. Expect the GC to first eat much more P.pusillus than other pond weeds. When P.pusillus is gone then other plants will be consumed with fervor.

In my experience long leaf pondweed (aka American pondweed) has a more elongate leaf than those in the picture. Best way to tell is send me some of the seeds for a positive ID. Either way which ever the name of this type of pond weed: long-leaf pondweed(P. nodosus), Illinois pondweed, Floating, Oakes, or Spotted pondweed all have similar structure, growth habits, and all with similar or same habitat benefits. IMO all being basically equal.

Bill C., how fast did partial control of the weeds happen after that one Grass Carp was stocked. What size was it at stocking?

Thanks Bill! I will send you some seeds. I assume the seed heads are the pods sticking above the surface. How will I know when the time is right to collect one to send to you?

I will also follow your recommendation and stock 1 grass carp this fall. I don't want to eliminate the vegetation, just keep it controlled.

"" how fast did partial control of the weeds happen after that one Grass Carp was stocked. What size was it at stocking? Grass carp was 10"-11" at stocking in the spring 2008. Denuding of smallpondweed took two years and three more years to eliminate the water lilies. A bare pond with more turbid water in 2014, 2015 and 2016.

The flower/seed head above the surface contains the seeds. Let it develop at the surface for 2-3 maybe 4 weeks and send 1 or 2 nice large ones to me. I will make a close examination of the individual seeds which are unique to each pondweed species. Hopefully the seeds are unique enough that speciation will be relatively easy. I have some long leaf pond weed so I can compare the actual seeds.

Bill,

Seed heads are on the way. I also sent a leaf, thinking that might be helpful. You should have them next week