Duckweed and watermeal are two very similar aquatic plants and many times are found together in the same water body. They are both free-floating plants that float around on the water surface. Once these weeds get established, they become difficult to eradicate. They spread rapidly across quiet water bodies and under ideal conditions; they can double their area coverage in a few days. They are extremely resilient and difficult to eradicate. Once a water body is covered with duckweed and/or watermeal, natural oxygen transfer from the atmosphere is greatly reduced. Many times this leads to massive fish kills and will restrict sunlight that native aquatic plants need to survive.
Once the surface is covered with these weeds, in addition to making a pond or lake unsightly and not very appealing for swimming, sunlight is prevented from reaching the deeper parts of the water body. Thus, reducing the ability of sub-surface plants to photosynthesize and produce oxygen, which in turn may reduce the levels of dissolved oxygen below the acceptable levels required for a healthy fish population. A strong odor may then develop and organic muck loaded with excess nutrients will accumulate. To keep a water body healthy, it’s best to keep them under control.
It is thought that duckweed can be used as a water purifier, as the plant consumes nitrogen and phosphorus from the water. Due to this nitrogen and phosphorus consuming quality you will find duckweed in many ponds that have problems with septic, agricultural and fertilizer run-off. But using duckweed for water cleansing is certainly a low tech and time-consuming process and duckweed cannot get rid of pesticides, heavy metals or toxic substances. Also, as mentioned above, duckweed can very quickly cover a whole pond and is very difficult to get rid of manually once it is overgrown.
Identifying Duckweed and Watermeal
Duckweed and watermeal are small, stemless, free-floating, aquatic flowering plants which grow across the world except in very cold regions.
Duckweed and watermeal normally do not grow in rivers unless there is a reduced flow of water. Generally, the reproduction rate of duckweed and watermeal are astounding given the right nutrient load in the water. It can cover 1 acre in just 45 days if left unrestrained
- Duckweed and watermeal are bright green and when fully grown can form carpet-like groups
- Common Duckweed has 1 to 3 leaves measuring 1/16 to 1/8 inches in length
- Giant Duckweed has 1 to 4 leaves measuring 1/16 to 1/4 inches in length
- 1 to 6 roots may grow from each “leaf”
How to Get Rid of Duckweed and Watermeal Naturally
While many people resort to chemicals to control duckweed and watermeal, the ideal solution is to manage duckweed without the use of chemicals as it can be disruptive to aquatic ecosystems and threaten native aquatic wildlife and plants. In addition, killing plants adds to the organic muck on the bottom and increases available nutrients. Many times, duckweed and watermeal return as more seeds germinate from the nutrient-rich muck. This creates a cycle involving multiple chemical applications and more dead plant biomass. However, natural solutions for eliminating duckweed and watermeal are not necessarily quick fixes in many circumstances due to the excessive nutrients available from years of abuse.
Aeration for Duckweed and Watermeal Control
Oxygen is the most important constituent of a lake or pond’s health, as it’s an essential element for all aquatic organisms that breathe. Therefore, there is a direct relationship between the oxygen concentrations and exchanges occurring in a lake or pond, and the physiological status of aquatic organisms. Without oxygen at the bottom of a pond or lake, anaerobic bacteria (those that live without oxygen) produce an acid environment. These acids not only increase acidity but also cause a massive release of phosphorus and nitrogen, two major fertilizers, from the organic sediment into the water column of the pond or lake. These fertilizers feed duckweed and watermeal increasing their quantity and density.
Aeration systems are ideal for oxygenating a lake or pond that has been overtaken by duckweed or watermeal. By increasing dissolved oxygen in an environment depleted of oxygen, water quality improves and fish and other aquatic wildlife thrive. Aerobic bacteria thrive off increased oxygen levels, resulting in improved water quality and natural decomposition of organic matter—reducing duckweed and other plant life.
CLEAN-FLO’s approach to natural control involves the use of laminar flow aeration. Our aeration technology is proven to oxygenate the entire water column and the organic sediments that cover the bottom. The Clean-Flo process of water body restoration provides a custom solution for providing aeration in your water-body from bottom to top.