Leafy elodea control

Page last updated: Friday, 4 October 2019 - 5:42pm

Control methods for leafy elodea (Egeria dansa) a declared pest in Western Australia.

REPORT THE PRESENCE OF THIS PEST BEFORE UNDERTAKING CONTROL

Information about this pest can be found on the leafy elodea: declared pest page.

Chemical requirements

When using any agricultural chemicals please ensure that you always follow instructions on the label and any permit. Users of agricultural chemical products must always strictly comply with the directions on the label and the conditions of any permit. To view permits or product labels go to the Australian Pesticides and Veterinary Medicines Authority website.

Control control options

There are no chemicals registered for this weed but these chemicals have activity on other aquatic weeds. Chemical control options can be found below. For other methods of control please refer to the aquatic weed control page.

Recommended herbicides

  • Diquat
  • Coptrol

Herbicide: Diquat (Group L) (various trade names: see APVMA link)

Active ingredient

200g/L diquat               

Rates of dilution for spot spraying

A concentration of 0.5-1ppm must be maintained throughout the entire water body

1ppm = 1mL diquat/m3

Amount of product/10L water

50mL

Rate of product/ha

5–10L product/ha/m depth

Wetting agent dilution

Not recommended

Time of application

Summer - when plant is actively growing

Remarks
  • Diquat should be sprayed on to or injected into still or slow moving water. Mixing of the water is desirable but do not stir up the mud. Do not use water for irrigation for at least 10 days.
  • Very high volume application 2500L/ha

More information and other control methods

Small infestations may be removed mechanically. Flowing water can be treated with Acrolein  (permit and licence required).

  • Drain channel or dam and treat with residual herbicides if not used for irrigation
  • Londax (100g/L bensulfuron) is being tested in the eastern states at 300–500g/ha

Herbicide: Coptrol

Active ingredient

107g/L present as mixed copper chelates

Rates of dilution for spot spraying

Adjust rates for other formulations

Rate of product/ha

2–5L spray to obtain correct dilution (see label for table to calculate dilution required for various depths of water)

Wetting agent dilution

Water temperature should be at least 15ºC

Time of application

Re-treat after 14 days if required. Full effects may take up to five days.

Remarks

  • Use for lakes, potable water reserves, farms, fish and industrial ponds, hatcheries ditches and canals
  • Care should be taken when treating water containing fish or crustaceans if hardness is less than 50ppm

Contact information

Pest and Disease Information Service (PaDIS)
+61 (0)8 9368 3080