Duckweed: What is it? How to Rid Your Pond of It.

by Patricia Foreman Discount Pumps

Hunters and wildlife enthusiasts may agree that both agree that ducks love Duckweed. Though this is true, there don’t love it enough to keep it from spreading throughout your pond.

Common Duckweed of the genus Lemna, is a small plant that floats slightly below the surface and on top of the water. When we see Common Duckweed, we typically see other species with it, particularly Giant Duckweed and/ or Watermeal. Duckweed can be one of the most invasive plants in your pond due their ability to reproduce. These plants live in fresh, mostly still water, but will grow anywhere fresh water is in the world, except in the coldest climates.

In Venezuela, in 2004, Duckweed covered a notable portion of Maracaibo, the country’s largest lake. The government sponsored a project for removal of the plants with mechanical skimmers, removing over 75% of the plant mass.

Although this sounds impressive, we need to understand that Duckweed can double itself approximately every 48 hours in warmer temperatures.

If you ever notice what appears to look like tiny leaves floating at the pond’s edge, pick them up and get a closer look. Duckweed typically has two little green leaves that are roughly half the size in diameter as a pencil eraser. Sometimes there is only one leaf, and sometimes there is as many as three leaves, but two leaves are more common. If you look closely, you will see tiny little white roots extending from the joint of the leaves.

Some aquarists like to use it for their aquarium fish. Certain areas of Southeast Asia use duckweed for human consumption as a source of protein. Some aqua culturists like to use it in their fish farms as a feed ingredient or to extract nutrients from the water to clean it up. University researchers are testing Duckweed as a potential source of renewable energy.

Recreational pond management does not care for duckweed for the same reasons other people like it – it will grow and spread fast. It can make its way to your pond by flowing downstream, or it can go for a ride on the feathers of a passing water bird. Your dog can bring it home with him after going for a swim in the neighbor’s pond.

Once it makes it to your water, it will reproduce either vegetatively or with its seeds. One plant will split into two, two into four and so on. So, you have a duckweed problem? What is a pond owner to do? How to get rid of duckweed? One way is to leave it alone, hope for a flood to wash it downstream, or hope that a winter freeze with eradicate the problem. Another is to physically remove by skimming the water or a pond fountain will help remove duckweed. The third is to use the least toxic approved herbicide to eliminate it efficiently.

Rule out using grass carp as a viable option. Though some individual grass carp may figure out how to tip their mouth upward enough to eat it, duckweed grows far beyond their abilities to control it. Forget out tilapia too. Tilapia will nibble on watermeal, but they have not been proven to be effective on duckweed.

When duckweed begins to rear its ugly head, a more realistic approach is to skim the water’s surface with a swimming pool net. However, you must catch it early and observe often with net in hand.

The third option – the use of herbicides. But, here is where things get a little tricky. Since duckweed floats on top and just below the water’s surface, you need to carefully consider your treatment options. Consider hiring a professional for advice or to perform the treatment for you. If you prefer to do the treatment yourself, be sure to do your research.

Key points to keeps in mind about duckweed. It floats, or at least some of it does, and it travels around. Surface contact herbicides like glyphosate will take multiple treatments.

Keep in mind that duckweed reprocess prolifically, so even after eliminating some of it, that does not mean that you have rid your water of it since it reproduces every 48 hours.

You may have desirable species of submerged plants in your pond that you would like to keep. Be certain that the herbicide you choose will impact the rest of your pond in a way that you expect. In other words, prep yourself for collateral elimination.

If you choose to use an herbicide, be sure to follow the labels directions and understand the repercussions of decaying matter in your beloved fishing hole. The last thing you want is oxygen depletion after the duckweed is gone.