Free Floating Aquatic Weed Control

Your Guide to Identifying & Controlling Free Floating Aquatic Weeds

There are three common types of Free Floating Aquatic Weeds

1. “Duckweed” or Lemna
Duckweed is a very common, tiny, free floating aquatic plant, with leaves varying from less than 1mm up to 1cm in size. Duckweed appears as a green cover on the waters surface and is an indication of nutrient-enriched conditions. It grows rapidly in stationary and slow moving water bodies, especially where nutrient levels are high. If not treated, it can double in numbers within five to seven days.

2. “Azolla” / Red Azolla / Green Azolla or Ferny Azolla
Azolla is another common free floating aquatic plant, with leaves varying in size from 1 to 2.5cm in diameter. Azolla appears in a greenish shade and can turn a reddish 
shade in the late afternoon or when exposed to full sunlight over a period of time. Azolla has a fern type leafed appearance with roots trailing below the waters surface. If not treated it can double in numbers within seven days.

3. Salvinia
Salvinia is a declared noxious free floating aquatic weed, in all states of Australia, with the plant measuring up to 20cm long and leaflets of 0.5-3cm wide. The leaves are covered with hairs that repel water and keep it from sinking. Salvinia is capable of choking a water body, it multiplies by fragmentation and can double the area it covers in five days. If not treated it can take over a water body, kill fish and rapidly affect water quality.

 

How to Control Free Floating Aquatic Weeds

Free floating aquatic weeds such as duckweed, lemna, azolla and in particular salvinia can be difficult to eradicate due to their rapid growth rates.

Effective methods of treatment can vary depending on the level of infestation. Treatments are most effective when the infestations are smaller rather than advanced.

The main methods of control include, spray treatments, physical removal and a combination of both.

Spray treatments are most effective when the infestations are smaller rather than advanced. A combination of both a spray treatment and physical removal is best when the infestation is advanced and is covering 90 -100% of the waters surface.

 

Free Floating Weed Control Spray

Free Floating Weed Control is an effective way to control Salvinia, Duckweed, Lemna and all types of Azolla.

It is a natural product based on orange oil extracts that is safe and easy to apply. It does not affect other aquatic plants and treated water is safe for use, as there is no withholding period. Water bodies treated with Free Floating Weed Control, are safe to use for irrigation and stock watering purposes and it is safe for fish, pets and wildlife as it is not a herbicide.

Free Floating Weed Control effects floating aquatic weeds in various ways, for Duckweed and Lemna it partially removes the wax coating on the leaf, thus reducing the leafs buoyancy. In the case of all types of Azolla it partially shrivels the tiny hairs on the leaf which trap air to keep them afloat. For Salvinia it effects both the wax coating and the tiny hairs that trap air.

In all cases Free Floating Weed Control effects the surface tension of the water, thus reducing buoyancy for all types of free floating aquatic weeds, making them lose buoyancy and sink in the water column and die.

 

Directions

Suitable for the control of Salvinia, Duckweed, Lemna and all types of Azolla, in lakes, dams, irrigation channels, water storages and ponds.

Depending on the density of the Free Floating Weed Control, it is beneficial to apply several light applications over 1- 3 week period, instead of one single heavy application.

Free Floating Weed Control is most effective when the infestations are smaller rather than advanced.

To ensure that the waters surface tension is effected, ensure that all for the open waters surface is treated. In areas where there is no free floating aquatic weeds, apply lightly but evenly.

If the infestation is advanced, an increased product to water mixing ratio can be used to increase the strength of the application.

If the infestation is advanced with 90 -100% coverage of the waters surface area, it is recommended that some of the free floating aquatic weeds are physically removed to create free water, to allow the free floating aquatic weeds to be able to sink effectively.

 

Application rates

1L of Free Floating Weed Control treats up to 500sqms of water surface area, depending on the density of the floating aquatic weeds.

To apply mix one part Free Floating Weed Control with 100 parts water and spray using a back pack sprayer or hose directly onto the free floating aquatic weeds and around the adjoining open water surface.

 

Free Floating Weed Parachute Skimmer

The physical removal of free floating aquatic weeds has several advantages particularly when infestations are advanced. Partial physical removal increases the effectiveness of spray applications, such as Free Floating Weed Control by creating free water to assist the weeds in sinking, reduce the amount of spray being applied and speed up the overall treatment process. Partial physical removal or bulk physical removal takes out the nutrient loading held within the free floating aquatic weeds.

The Free Floating Weed Parachute Skimmer is specifically designed to make the job of physically removing Salvinia, Duckweed, Lemna and all types of Azolla quick and easy.

Safe and simple to use, the skimmer reduces the OH&S risks with its easy action to capture free floating aquatic weeds and remove them from the water.

Each sweep, captures a path using a tailored screen mesh and as the skimmer is removed from the water it closes and traps the catch, for easy disposal onto the shore line or into a wheelbarrow or trailer.

The Free Floating Weed Parachute Skimmer is available in two sizes and two specific mesh types, each mesh type is specifically tailored to the type of free floating aquatic weed being removed.

The large skimmer clears a path of 91cm wide with every sweep and is ideal for ponds and dams.

The Industrial skimmer clears a path of 1.52m wide with every sweep and is ideal for larger water bodies or to clear smaller water bodies more quickly.

Both the large and industrial size skimmers are available with specific mesh sizes designed for the effective capture of different types of free floating aquatic weeds.