Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants cypress trees / diquat/water spangle

I have met someone here in FL that recently pucrhchased land with a pond. The previous owner appearnlty dumped an aqaurium in the pond and the auarium plants in it has totally covered the pond. He researched what it is and now I can't remember.

He sprayed it with a glyphosate aquatic herbacide. It killed what it touched of coarse and did not kill any thing in or under the water and its growning back. I pointed out using one that with diquat would effect the submerged plants for him better then glyphosate.

My question is.....He asked if it would effect the cypress tress around the ponds edges, I didnt think so but I am not 100% sure.

I also recomended pond boss as a better resource than me on plants.

Once he can actually see the water, I'm hopeing he will let me help him out on the fish side of things..:-)

Diquat would only affect the surrounding trees if physical drift was allow to contact the trees' foliage, and even then the impact would likely prove only temporary.
Whether diquat would would actually benefit the aquatic weed situation greatly depends upon the weed's identity.

Ill find out what it is exactly and report back

In the pet stores its called water spangle, Salvinia Minima we believe. It covers pond totally, Will aquatic Herbiside with Diquat kill it?

Also will GC help?
Tilapia?

Reward (Diquat) will work, but Clearcast or Galleon is a more effective option (I think).

I doubt you'll see effective control with biologicals without them working on a lot of other plants first.

Hopefully Kelly will chime in soon.

Bobby - Are you absolutely certain that it is Salvinia minima (Common Salvinia) and not Salvinia molesta (aka Giant Salvinia)? This may sound like a trivial question, but it does matter since the former is considered a native species while the later is now one of the most feared exotic/invasive aquatic surface-weeds due to its extremely aggressive and prolific propagation within infested water-bodies.
Using a hand-lens/magnifier, look at the pubescence (hairs) on the plant's leaf surface. If the hairs terminate with straight ends, you have S. minima. If the hairs split and reform at the tip - producing the appearance of "egg-beaters" - you have S. molesta. See photo below.
Treatments are the same for both, but you're wise to take extra urgency in controlling the plant if it turns out to be molesta.

thanks kelly we will look to see if we can figure that out just so we know,

What might be the best treatment ??


this sound about right?

Reward (Diquat) will work, but Clearcast or Galleon is a more effective option...................

Actually, glyphosate combined with a relatively low rate of diquat is probably your best option for both species. However, the referenced hairs provide the plant with a very effective physical barrier against spray-deposition ---- the same goes for water lettuce. It is vital to tank-mix a good quality "conventional aquatic surfactant" AND an organosicone surfactant with the glyphosate/diquat mixture. The former enhances leaf-cuticle uptake, but that function won't happen unless the droplets penetrate through the dense leaf-hairs - which is the function performed by the organosicone surfactant.
My company has several locations scattered around FL, in case you have any difficulty locating the necessary adjuvants for this type of treatment.