How to Remove Dam Weeds

Owning a rural property with a dam that serves as the nucleus for an efficient agricultural operation is a dream for many. However, general maintenance and keeping the dam weed-free can quickly become a nightmare. The truth is, that maintaining a clean and efficient dam requires continued effort and know-how, so we’ve created this introductory guide to managing the aquatic weeds that can rapidly plague farm dams. We’ll have a look at the most effective strategies for removing dam weeds so that your farm’s water body remains pristine, inviting, and most importantly, effective.

Farm dams can quickly succumb to the unrelenting spread of aquatic plants, particularly if you’re unable to contain the spread of weed seeds.  Water weeds have tenacious roots and prolific growth habits and will almost certainly mutate a once-idyllic dam into a tangled jumble of vegetation that chokes rivers and degrades water quality. A range of aquatic species, including water hyacinth and alligator weed, provide considerable problems to dam ecosystems for both professional and hobbyist farmers. 

Categories of Aquatic Plants

Aquatic weeds can be classified into several categories based on their growth habits and habitat preferences. Emergent, free-floating, floating leaf, perennial grass’ and submerged weeds, each present unique challenges and require tailored control methods.

Emergent weeds, such as cumbungi and arum lily, grow stems and leaves above the water surface and will often be found along the dam’s edges. On the other hand, free-floating weeds, like salvinia and water lettuce, have a tendency to drift on the water’s surface, while floating leaf weeds, such as water lilies, are rooted in the soil but have long stems that stretch to the surface. Submerged weeds, including pond weeds and elodea, grow entirely beneath the water and are rooted in the soil.

Among the most persistent offenders are floating weeds that seemingly proliferate overnight. If you’re a dam owner reading this article to seek advice on invasive floating weeds in your dam, chances are you either have a duckweed or water lettuce problem. Their tiny size and rapid reproduction form a dense mat that smothers the water surface, blocking sunlight and oxygen from reaching the depths below. These floating weeds outcompete native plants and disrupt the balance of the aquatic ecosystem of your dam. 

Another problem you may be facing, aside from relentless floating weeds, is submerged weeds. Amid the encyclopedia of invasive weeds, emerges perennial grasses, which have an extensive rhizome system, and like bullet grass, have a tendency to spread across the dam floor and send shoots upward to the surface of the water. If it’s not perennial grasses that are causing problems to your dam, you may be suffering from the colonisation of other submerged weeds like pondweed and elodea. 

So, what’s the solution? I hear you ask defeatedly. Fear not there are a multitude of options available. From mechanical, biological, and chemical solutions, you can equip yourself with an arsenal of defenses against the seemingly never-ending onslaught of invasive aquatic weeds. Whether you opt for the more physical approach of mechanical control, using tools such as weed rakes and aquatic weed cutters, or decide to take things biological/ chemical by using products such as Reglone, rest assured that there is an abundance of solutions out there. 

Aquatic Weed Control

A three-stage decision process is recommended for controlling aquatic weeds in farm dams. Initially, farmers may choose to do nothing if the weeds are not blocking essential infrastructure. If mechanical removal becomes necessary, options include dragging the dam with mesh or ringlock or using Reglone for submerged weeds as a last resort.

Mechanical or Manual Removal

Attempting to remove dam weeds via manual methods or mechanical tools should often be your first line of defense. While this approach can be surprisingly effective, particularly for smaller infestations, it can also be rather labour-intensive. 

Manual removal is a practical and environmentally friendly approach to controlling dam weeds. By manually removing weeds from the water and disposing of them properly, you can prevent further spreading and promote a healthy aquatic environment. Additionally, regular maintenance, such as trimming and thinning out aquatic plants, can help keep dams in peak condition and attract an array of wildlife.

Methods, such as cutting, mowing, and dredging, can be effective in small areas where chemical control is not suitable. However, mechanical control can be expensive and may spread weeds if not done carefully.

Tools such as an  Aquatic Weed Cutter,  a Beachroller, or a DeSkuzzer 2.0 offer an efficient way to clear floating and submerged weeds, without the backbreaking labour that comes with this approach. 

These kinds of tools offer you a quick and efficient means to maintain water quality and maximise dam weed removal with minimal effort, whilst saving you from jumping into your infested farm dam wielding a machete.

Aeration

Aeration is another cost-efficient and effective way to reduce dam weeds. The process improves the dam ecosystem by introducing oxygen to the water body for good bacteria to grow. These bacteria absorb nutrients such as nitrogen and phosphorus, which are required for weed development. Farmers should aim to establish an environment in which weeds struggle to flourish by maintaining appropriate aeration.

Probiotics & Biotism Accelerators 

Feeding probiotics to the dam habitat can help with weed control efforts. Probiotics promote the growth of good bacteria, which reduces the nutrient levels at which aquatic weeds thrive, in turn creating an unfavourable environment for weed growth. This solution allows you to efficiently starve out weeds and keep them away by following an aeration and probiotic routine.

 

Chemical control

The use of chemical herbicides should be the last resort when dealing with invasive aquatic weeds and weed seeds. While it is true that chemicals such as Glyphosate, Reglone, and Dichlobenil can provide rapid results, you are, in essence introducing a chemical poison to your dam’s natural ecosystem which can cause severe damage to the habitats of other animals that share your water body and harm ecosystems further downstream.

If you are left with no other choice than to use chemical herbicides to tackle your dam weeds, we recommend using a product like WaterTreats Aquatic Weed Killer in tandem with Biostim Accelerator. The Biostim Accelerator reduces how much chemical you need to use.

Preventing Aquatic Weed Growth 

Implementing preventative measures is critical to lowering the risk of aquatic weed development in farm dams. You should consider implementing strategies such as silt traps, which aim to intercept sediment flow, avoiding the buildup of organic matter, which acts as a fertiliser source for weed growth. Silt traps capture sediment before it reaches the dam, reducing not only the input of nutrients but also the development of weed seeds carried by sediment particles.

The ideal scenario and goal should be maintaining the high water quality of your dam as it is critical in limiting the spread of aquatic weeds. Regular monitoring of water parameters such as pH, dissolved oxygen levels, and fertiliser concentration will enable you to detect possible imbalances that promote weed development. 

Conclusion

To summarise, the importance of managing the presence of aquatic plants and dam weeds goes beyond aesthetics; keeping the water body of your dam clean is crucial to safeguarding the structural integrity of your dam, as well as optimising the efficiency of your agricultural operation. 

You should aim to implement a multi-faceted, comprehensive approach to weed management by incorporating mechanical and biological preventative measures that can mitigate the proliferation of aquatic weeds. As a last resort, if all else fails, there remains the option to introduce chemical herbicides. 

Through diligent efforts to curb the scourge of various weed species, including targeted removal of dam weeds and the implementation of preventative measures, you can ensure the long-term health and productivity of your farm dam.