Aquatic Weed Treatments: What Are Your Options?

Aquatic weeds can be a nightmare for your dam. Not only do they make your dam look less than inviting, but these water weeds can have a negative impact on your water quality, human activities, and the ecosystem as a whole.

Aquatic weeds differ from aquatic plants or pond plants, but the differences can be difficult to understand unless you’ve done a bit of research.

In this article, we’re going to make it easier for you. We’ll help you learn the difference between pond weeds, floating leaves and aquatic plants, and by the end of this guide, you’ll know how to treat the different types of aquatic weeds in your dam. Take a look below to learn more now.

What are Aquatic Weeds? Different Types and Species to Watch Out For

Aquatic weeds are plants that grow in or near water bodies, like your dam. They can be both native species and invasive species and can have a negative impact on your aquatic ecosystem. Common characteristics of aquatic weeds include the following.

• Adaptations that make water living easy for them: Often, this means these aquatic plants have specialised structures that allow for buoyancy, nutrient uptake, and reproduction in aquatic conditions.
• Quick growth: Aquatic weeds often have fast growth rates, which makes it easy for them to form dense mats on the water’s surface.
• Impact on the ecosystem: This might mean displacing native vegetation and pond plants, inhibiting water flow, or affecting the nutrient cycling in your dam.

While these are general characteristics, there are subcategories of water weeds that you will need to know about to be able to treat them as effectively as possible. We’ve gone into them in more detail below.

Floating Weeds

Floating weeds, as the name suggests, are plants that grow on or near the water surface and float freely. They have buoyant structures and floating leaves that allow them to stay afloat at all times. Their root systems tend to be shallow, and they grow very quickly.

Floating weeds can emerge in many different types of water bodies and often are adapted to allow them to deal with fluctuations in water depth. Some common floating weed types include duckweed, water hyacinth, and water lettuce.

Emergent Weeds

Emergent weeds are the sort of in-between of floating and submerged weeds. They grow in and around the margins of water bodies, like dams and lakes. Their stems, leaf stalks, and flowers extend above the water surface, but the roots tend to remain submerged or in contact with the water.

These aquatic weeds have vegetative parts that extend above the surface of the water, allowing them to capture sunlight and gases from above the surface of the water. The roots are adapted to allow for stability and nutrient uptake in the water. In some cases, this can prevent soil erosion along the water line. However, if these pond weeds grow out of control, it can cause a problem.

Emergent weeds tend to offer shelter and a livable habitat for both aquatic and terrestrial species. Some common emergent weed types include cattails and water lilies.

Submerged Weeds

Submerged weeds grow entirely under the water surface, so everything from their stems to flowers to leaves grow underwater. These pond plants tend to have thin and flexible stems and delicate leaves, helping them to survive underwater.

Submerged water weeds obtain oxygen and nutrients from the water directly through their tissues and play a role in the nutrient cycling in the dam. Often, aquatic life, including fish, invertebrates, and microorganisms, live in these water weeds.

Common submerged weeds include pondweeds, elodea, and eelgrass.

Treating the Different Aquatic Weeds in Your Dam

There are many ways to tackle an overgrowth of water weeds in your dam, and these include both manual removal and the application of products like Biostim. Below, we’ve given you an idea of the kind of treatment you need for each kind of weed.

Treatment for Floating Weeds

For floating weeds, we always recommend starting off manually. This means using a product like a DeSkuzzer or a pond net to drag as many of the water weeds as you can from the surface of the water. For extreme infestations, use ProSkim. When removing manually, always wait for the day after a windy day so all the weeds have gathered together.

After manual removal, it’s time to treat the cause of an overgrowth of water weeds. Often, if you have lots of weed matter that forms dense mats on your water surface, then the problem is too many nutrients in your dam. So, to stop an overgrowth again, you need to reduce the nutrients in your dam.

There are two ways to do this, which can also be combined for a heavy infestation.

• Aeration: Aerating your dam means introducing more oxygen into the water. This creates ideal conditions for aerobic bacteria, which reduce the nutrients in your dam and starve the weeds.
• Biostim: Our Biostim range includes pellets, tablets, powders, and liquids. it is a probiotic treatment that stimulates the aerobic bacteria in your dam, increasing their populations and eventually starving the weeds.

Biostim works even more effectively when coupled with aeration, so consider pairing an aerator with our Biostim Pellets.

Treatment for Emergent Weeds

For emergent weeds, you need to manually remove them using either your hands for young and soft plants; an aquatic weed hand cutter, for hardier plants, or a lake bottom blanket, for spot treatments. After you have manually removed as much as possible, you will need to use the same process as above to reduce the nutrients in your dam. This means using Biostim products, like Biostim Powder, and aeration products, like the Matala AirStation.

Treatment for Submerged Weeds

As above, you first need to manually remove as much of the submerged weed as you can. To remove these submerged weeds, try a lake bottom blanket for spot treatments to starve them of sunlight, a beachroller for soft-celled plants to till the soil and slow regrowth, or an aquatic weed hand cutter for hardier plants.

Using dam dye can help you to see where the weeds are most concentrated in your dam, making the manual removal process much easier.

Next, you need to treat the root of the problem; the nutrients in your dam. This treatment is exactly the same as above and includes either aeration, Biostim liquid or a combination of both.

When to Treat the Aquatic Weeds in My Dam

As there are cases when aquatic weeds can have benefits for natural waterways, it can be difficult to know whether or not you need to treat your weeds. Below are some ways you can tell that you have a weed problem.

• You’ve noticed mats of plants covering the surface of your water.
• The water appears discoloured; for instance, it is dark green, brown, or cloudy. Note: If your water is bright green, you may have an algae problem, not a weed problem.
• Water flow is obstructed in natural waterways.
• You’ve noticed a change in aquatic life, i.e., there are fewer fish and aquatic creatures due to the decreased oxygen levels.
• Weed fragments have been washing ashore.

Final Thoughts

Aquatic weeds are split into three types; floating, emergent, and submerged. Each can have benefits for the ecosystem in your dam, but overgrowth can lead to depleted resources and an impact on the ecosystem as a whole.

We’ve given an overview of how each type of weed can be treated using our kind and non-toxic products. For more information, remember to check out our YouTube channel.