Water lilies (Nymphaea species)

Also known as: water lily

Water lilies are aquatic perennial plants. Several species have escaped cultivation.

Biosecurity duty

This plant is a water weed
This plant is not to be sold in all or parts of NSW

Profile

How does this weed affect you?

Water lilies are regarded as an environmental weed in NSW and Qld. Waterlilies have escaped cultivation and have become a weed of freshwater habitats where they displace similar native species and blocks waterways.

Control

Herbicide options

WARNING - ALWAYS READ THE LABEL
Users of agricultural or veterinary chemical products must always read the label and any permit, before using the product, and strictly comply with the directions on the label and the conditions of any permit. Users are not absolved from compliance with the directions on the label or the conditions of the permit by reason of any statement made or not made in this information. To view permits or product labels go to the Australian Pesticides and Veterinary Medicines Authority website www.apvma.gov.au

See Using herbicides for more information.

Diquat 20 g/L (Watrol®)
Rate: 4.0 L per 100 L of water
Comments: Apply as an overall spray. Thoroughly wet foliage. Best if clean water is used; higher rate if dense weed or dirty water. Observe withholding period.
Withholding period: 1 day in pasture, 10 days in treated water.
Herbicide group: L, Inhibitors of photosynthesis at photosystem I (PSI inhibitors)
Resistance risk: Moderate

Diquat 20 g/L (Watrol®)
Rate: 50–100 L/ha
Comments: Apply as an overall spray. Thoroughly wet foliage. Best if clean water is used; higher rate if dense weed or dirty water. Observe withholding period.
Withholding period: 1 day in pasture, 10 days in treated water.
Herbicide group: L, Inhibitors of photosynthesis at photosystem I (PSI inhibitors)
Resistance risk: Moderate

Diquat 200 g/L (Reglone®)
Rate: 400 mL per 100 L of water
Comments: Add Agral 600 wetter; use clean water for best results. Observe withholding period.
Withholding period: 1 day in pasture, 10 days in treated water.
Herbicide group: L, Inhibitors of photosynthesis at photosystem I (PSI inhibitors)
Resistance risk: Moderate

Diquat 200 g/L (Reglone®)
Rate: 5.0–10.0 L/ha
Comments: Add Agral 600 wetter; use clean water for best results. Observe withholding period.
Withholding period: 1 day in pasture, 10 days in treated water.
Herbicide group: L, Inhibitors of photosynthesis at photosystem I (PSI inhibitors)
Resistance risk: Moderate

Glyphosate 360 g/L (Only products registered for aquatic use)
Rate: 1 L to 100 L of water
Comments: Re-treat unaffected plants.
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate

Biosecurity duty

The content provided here is for information purposes only and is taken from the Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.

Area	Duty
All of NSW	General Biosecurity Duty All plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable.
Central West	Regional Recommended Measure* Land managers should mitigate the risk of new weeds being introduced to their land. The plant should be eradicated from the land and the land kept free of the plant. The plant should not be bought, sold, grown, carried or released into the environment. Notify local control authority if found. *This Regional Recommended Measure applies to Nymphaea mexicana* (Mexican water lily)**
Murray	Regional Recommended Measure* Land managers should mitigate the risk of new weeds being introduced to their land. The plant should not be bought, sold, grown, carried or released into the environment. Notify local control authority if found. *This Regional Recommended Measure applies to Nymphaea mexicana* (Mexican water lily)**
North West	Regional Recommended Measure* Land managers should mitigate the risk of new weeds being introduced to their land. The plant should be eradicated from the land and the land kept free of the plant. The plant should not be bought, sold, grown, carried or released into the environment. Notify local control authority if found. *This Regional Recommended Measure applies to Nymphaea mexicana* (Mexican water lily)**
Northern Tablelands	Regional Recommended Measure* Land managers should mitigate the risk of new weeds being introduced to their land. Land managers should mitigate spread from their land. The plant should not be bought, sold, grown, carried or released into the environment. Notify local control authority if found. *This Regional Recommended Measure applies to Nymphaea mexicana* (Mexican water lily)**
Riverina	Regional Recommended Measure* The plant should be eradicated from the land and the land kept free of the plant. Land managers should mitigate the risk of new weeds being introduced to their land. The plant should not be bought, sold, grown, carried or released into the environment. *This Regional Recommended Measure applies to Nymphaea mexicana* (Mexican water lily)**
	*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfill the general biosecurity duty for this weed click here

For technical advice and assistance with identification please contact your local council weeds officer.
For further information call the NSW DPI Biosecurity Helpline on 1800 680 244 or send an email to weeds@dpi.nsw.gov.au

Reviewed 2018