Watershield, Water Shield Pond Weed

In this article we’ll go over what it is and various ways to manage this pond plant/weed, Water Shield

Watershield covering the pond

Watershield covering the pond

Rooted on the bottom of the pond with long stems reaching the surface producing an oval shaped leaf with a tiny sprout for a flower. Not actually a flower but a stem with a bunch of spikes from the center.

Water Shield is similar to Lilies  but not near as big of a leaf as the lilies have and of course lilies actually have a flower.

Watershield has a defense mechanism from chemicals, generally later in the year a gelatinous sheath forms around the stem to protect the stem. It’s a clear substance sort of like jello but sticks on the plant stems better than jello would. The stem is also very stretchy, almost like a rubber band, it will stretch to a certain point and finally snap. I guess we could use the example of spaghetti a well, since it will stretch and snap too.

Watershield can take over the entire pond depending on how deep the water is. Sort of

Watershield on 2 acre pond

Watershield on 2 acre pond

strange to see a pond covered in water shield except for one area clear. Nine foot and deeper Watershield does not seem to grow in these depths.

Controlling or managing this plant/weed manually will take some work, actually intensive manual labor by cutting then removing the plant from the water and relocating it to where it will dry out and die and not be able to wash or blow back into the pond.

Watershield cutting with Lake Mower

Watershield cutting with Lake Mower

Just like any other plant, weeds, even grass grows back after cutting. Water shield will do the same. If you have a small pond it may be possible to cut and remove the watershield each year to keep the surface of the pond clear but depending on your growing season you might need to cut twice or will be for sure cutting it again the following year. A two acre pond as seen in the picture will be good few days work cutting by hand or even with the Lake Mower.

Last resort is chemical / herbicide treatments, but which one to use? We covered the details in our post Pond Herbicide Treatments   But in short there are two types of herbicides and plenty of manufacturer’s whom have various chemical names to help control the Watershield.

The two types are classified as a contact or systemic herbicide. The contact needs to come in contact with the growing part of the plant in order to control the plant such as the leaves effectively killing the leaves and knocking back the plant growth. Re growth will happens again. But these contact type herbicides are less expensive and more available tot he home owner. while the systemic herbicide is more expensive but affects the stem of the plant and gets to the roots of the plant for a longer kill of the plant.

With any herbicide application we only want to do 1/4 to 1/3 of the pond at a time a as

watershield mixed with lilies

watershield mixed with lilies

the decaying plant will consume the oxygen from the water column, which will end up in a fish kill. We’ve seen this happen and was able to help the folks out to save a lot of his fish. Imagine seeing your prize bass and catfish going belly up and hauling away two wheel barrels with of dead fish.

Proper sized aeration in the pond will help a lot keeping the oxygen levels up and also helps to distribute the herbicide thought the pond as well.

I did not list herbicides, chemicals in this article due to the variety of them and depending on the pond owners plans to control their weeds. I also don’t stock many herbicides for the same reason that there are just to many to have on hand.

Ready to treat Watershield whats missing

Ready to treat Watershield whats missing

If you wish to go the route of using a herbicide use our contact page and let us know what you are dealing with. I can help you with selecting and other needed thoughts before purchasing.

One last issue with herbicides is the shipping some are classified as hazardous which will cost a little more on shipping. Then there are current states that have Restrictions. Alaska, California, Connecticut, District of Columbia, Hawaii, Maine, Michigan, New Jersey, New York, Puerto Rico, Rhode Island or Washington.

About the Author: Darrell Rhoades is the founder of Whatpond.com. A one man business, works full time in tool & die. It all started when he built his own pond for the family. Ran into pond issues and started the research with pond suppliers and conferences for pond management. He writes about pond building and pond management and sells pond management supplies, aeration & fountains and Practical hands on experiences at Whatpond.com. . No physical store, but has items in stock.

Comments on this entry are closed.

  • Heidi Ludwig Mar 15, 2021 @ 18:09

    I have watershield from top to bottom in my 3 acre pond. I’m hoping to completely eliminate this weed so it can be a swimming hole. I don’t have any fish to worry about but I do have ducks, geese and other wild life I don’t want to hurt. I love in Washington state and bought the property 6 months ago. We are starting to get warm weather and hoping to eliminate this before summer. What product would you suggest and how much?

  • Darrell Rhoades Mar 16, 2021 @ 9:05

    Hello Heidi,

    I will be more than happy to answer questions. Please use the contact page to get into private email. When you do please let me know what state you are in. Depending on the state laws and herbicide will determine if herbicides can be shipped in and or which herbicides as well. If you are in the northern states and the Watershield is either dead or maybe just starting to grow we do have time. The water shield wild need to be growing in order for the herbicides to work. Is the entire pond surface covered and what depth is the pond? Please answer these questions using the contact page.

    Thank you Darrell