Lobed needle grass (Nassella charruana)
Lobed needle grass is a tussock-forming perennial grass. It can form dense infestations which exclude other more desirable species.
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How does this weed affect you?
Even in its native Argentina, where the relatively unpalatable serrated tussock and Chilean needle grass are used as fodder, lobed needle grass is regarded as a serious weed due to its invasiveness and competitiveness. It is drought tolerant and forms dense infestations.
Where is it found?
Lobed needle grass is native to Uruguay, Argentina and southeastern Brazil. Its known distribution in Australia is limited to a few small infestations on the northern outskirts of Melbourne.
How does it spread?
Lobed needle grass reproduces by seeds. Although the exact amount of seed produced is not known, both of the closely related species serrated tussock (N. trichotoma) and Chilean needle grass (N. neesiana) can produce tens of thousands of seeds per plant per year. The seeds are very sharp and clinging, and readily attach themselves to clothing, fur and equipment. Seeds can also be spread when soil is moved. Major roadworks near the site of one infestation led to the spread of lobed needle grass. Anecdotal evidence suggests that the seed is not carried by wind like serrated tussock.
What does it look like?
Lobed needle grass is a type of spear grass. It is a perennial tussock-forming grass growing to about 1 m high. The leaves are narrow and rolled inwards and, like other tussock grasses, grow from the plant base.
The leaves possess a short (1 mm) transparent ‘ligule’, which is a small flap at the junction of the leaf blade and the leaf sheath. The ligule can be located by tracing a leaf down to where it joins the sheath and bending the leaf back at this point.
It has a single flower on each spikelet enclosed by two distinctive lobes. The body of the seed is 4–10 mm long and less than 1 mm wide. The bristle-like tail of the seed (the ‘awn’) is 45–85 mm long and well connected to the seed body at the ‘corona’, which is a long (up to 10 mm) white collar at the seed base.
What type of environment does it grow in?
Stipoid grasses (such as the Nassella species) generally invade sites that are already highly degraded with a history of disturbance, especially land with higher fertility soil that has been used for grazing or farming. Lobed needle grass has invaded open woodlands and native and introduced grasslands including grassland dominated by four other Nassella species. It grows mainly in open areas, in direct sunlight or light shade, on clay soils – its preferred soil type in South America. It is tolerant to waterlogging and appears to prefer wet depressions, but it also occurs on stony rises.
Acknowledgements
CRC for Australian Weed Management: David McLaren (DPI Vic/Weeds CRC), Linda Iaconis (DPI Vic), Neville Walsh (Vic Herbarium) and John Thorp (National Weeds Management Facilitator), David Cooke (APCC).
More information
Control
Because there are relatively few lobed needle grass infestations, and it can potentially be eradicated before it becomes established, any new outbreaks should be reported immediately to your local council weed officer. Do not try to control lobed needle grass without their expert assistance. Control effort that is poorly performed or not followed up can actually help spread the weed and worsen the problem.
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
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.
PERMIT 9792 Expires 30/11/2025
Flupropanate 745 g/L
(Tussock®)
Rate: 100 to 300 mL per 100 L of water
Comments: Spot spray control. Apply to actively growing and stress free plants. Apply once per year. See label for further critical use comments.
Withholding period: Spot spray: Do NOT graze or cut for stock feed for at least 14 days. Blanket spray: Do NOT graze, or cut for stock feed for at least 4 months. If stock are grazed in treated areas after required time has passed, remove stock from treated areas and do NOT slaughter or milk for human consumption until they have been on clean feed for at least 14 days.
Herbicide group: J, Inhibitors of fat synthesis (Not ACCase inhibitors)
Resistance risk: Moderate
PERMIT 9792 Expires 30/11/2025
Flupropanate 745 g/L
(Tussock®)
Rate: 500 mL per 10 L water
Comments: Wiper suppression
Withholding period: Spot spray: Do NOT graze or cut for stock feed for at least 14 days. Blanket spray: Do NOT graze, or cut for stock feed for at least 4 months. If stock are grazed in treated areas after required time has passed, remove stock from treated areas and do NOT slaughter or milk for human consumption until they have been on clean feed for at least 14 days.
Herbicide group: J, Inhibitors of fat synthesis (Not ACCase inhibitors)
Resistance risk: Moderate
PERMIT 9792 Expires 30/11/2025
Glyphosate 360 g/L
(Various products)
Rate: 3 L per ha
Comments: Broadacre control
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate
PERMIT 9792 Expires 30/11/2025
Glyphosate 360 g/L
(Various products)
Rate: 1 L per 100 L of water
Comments: Spot spray
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate
PERMIT 9792 Expires 30/11/2025
Glyphosate 360 g/L
(Various products)
Rate: 3.3 L per 10 L water
Comments: Wiper suppression
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate
Flupropanate 745 g/L
(Tussock®)
Rate: 1.5 to 3 L per ha
Comments: Broadacre control. See label for critical use comments.
Withholding period: Spot spray: Do NOT graze or cut for stock feed for at least 14 days. Blanket spray: Do NOT graze, or cut for stock feed for at least 4 months. If stock are grazed in treated areas after required time has passed, remove stock from treated areas and do NOT slaughter or milk for human consumption until they have been on clean feed for at least 14 days.
Herbicide group: J, Inhibitors of fat synthesis (Not ACCase inhibitors)
Resistance risk: Moderate
Flupropanate 86.9 g/kg
(GP Flupropanate)
Rate: 22.5 kg/ ha
Comments: Apply February to December inclusive. Apply to actively growing and stress free plants. Graze to reduce cover of desirable species before application.
Withholding period: Do not graze or cut for stock feed areas which have received any treatment other than spot treatment for at least 4 months. Spot treatment: Do not graze or cut for stock feed for at least 14 days. If stock are grazed in treated areas after required time has passed, remove stock from treated areas and do NOT slaughter or milk for human consumption until they have been on clean feed for at least 14 days. This requirement applies permanently to treated areas.
Herbicide group: J, Inhibitors of fat synthesis (Not ACCase inhibitors)
Resistance risk: Moderate
Flupropanate 86.9 g/kg
(GP Flupropanate)
Rate: 2.25 g per square metre
Comments: Spot application: apply year round. Apply to actively growing and stress free plants. Graze to reduce cover of desirable species before application.
Withholding period: Do not graze or cut for stock feed areas which have received any treatment other than spot treatment for at least 4 months. Spot treatment: Do not graze or cut for stock feed for at least 14 days. If stock are grazed in treated areas after required time has passed, remove stock from treated areas and do NOT slaughter or milk for human consumption until they have been on clean feed for at least 14 days. This requirement applies permanently to treated areas.
Herbicide group: J, Inhibitors of fat synthesis (Not ACCase inhibitors)
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 pest 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. |
For technical advice and assistance with identification please contact your local council weeds officer.
Reviewed 2021
