False yellowhead (Dittrichia viscosa)
False yellowhead is a perennial shrub with bright yellow flowers. It outcompetes other plants and can cause severe skin irritations.
Profile
How does this weed affect you?
False yellowhead:
- outcompetes native plants
- competes with pastures, reducing productivity
- is toxic to livestock, though rarely eaten
- can cause mouth and stomach injuries to animals that eat the flowerheads
- produces sticky oil in the leaves and stems which can cause itching and blistering skin.
What does it look like?
False yellowhead is an erect, perennial, soft-wooded shrub, 1–1.5 m tall and 1 m wide.
Leaves are:
- greyish-green
- oval-shaped with pointed tips
- 2.5–10 cm long and up to 3 cm wide
- serrated along the edges
- stalkless and the leaf base is half-wrapped around the stem
- covered in sticky hairs and release foul smelling oil when crushed.
Flowers are:
- bright yellow
- daisy-like with 12–18 petals (each 10–2 mm long)
- surrounded by 30–40 narrow, triangular, sticky bracts (each 3–9 mm long)
- present in summer and autumn.
Seeds:
- are 2 mm long
- have 15–25 bristles on one end.
Stems are:
- covered with glandular hairs which exude a sticky foul-smelling oil when young
- woody when older.
Roots:
- consist of a large taproot with many lateral roots, even on small plants, making the plant difficult to pull out.
Similar looking plants
False yellow head looks similar to other weeds including:
- Stinkwort (Dittrichia graveolens), which is an annual plant that has smaller flowerheads with 10-12 petals (4-7 mm long).
- Telegraph weed (Heterotheca grandiflora), which is a taller annual plant up to 2 m. It has many (25-35) smaller petals (5-8 mm long).
Where is it found?
False yellowhead has not been found in NSW. It is present in southern Western Australia.
It is native to southern Europe, the Middle East and Northern Africa.
What type of environment does it grow in?
False yellowhead grows best in high rainfall areas, however it is drought tolerant. It can grow on clay and sandy soils and tolerates saline soils. Plants usually grow in highly disturbed sites including roadsides, firebreaks and walking trails. They have also been found in swamps.
How does it spread?
False yellowhead spreads by seed. Most seed is spread by wind or water. Seeds can also be spread via earth moving machinery.
Germination often occurs after disturbances including earth moving or fire.
References
Identic Pty Ltd. and Lucid (2016). Weeds of Australia Fact sheet: Dittrichia viscosa (L.) Greuter Retrieved: 29 June 2026 from: https://keyserver.lucidcentral.org/weeds/data/media/Html/dittrichia_viscosa.htm
Cooperative Research Centre (CRC) for Australian Weed Management. (2003). Weed Management Guide: False yellow head (Dittrichia viscosa). CRC for Australian Weed Management.
Tasmanian Government (n.d.) Weed Risk Assessment: Dittrichia viscosa. Retrieved: 29 June 2026 from: https://nre.tas.gov.au/Documents/Dittrichia-viscosa-assessment.pdf
Sladonja, B., Poljuha, D., Krapac, M., Uzelac, M., & Mikulic-Petkovsek, M. (2021). Dittrichia viscosa: Native-non native invader. Diversity, 13(8), 380.
More information
Control
Because false yellow head has not been found in NSW, please contact your local council weed officer if you think you have found it.
Physical removal
The plant has large roots even on small plants therefore it is best to dig out plants rather than try to pull them out.
Herbicide control
Spot spraying
Apply to actively growing plants. Ensure that all of the foliage is thoroughly covered with the herbicide mix.
Splatter gun
Splatter guns use small amounts of concentrated herbicide. They spray large droplets that limit spray drift. They are useful for very dense infestations of weeds that are difficult to reach.
Weed wipers
Wipers or wands apply herbicide directly onto leaves. This method can target the individual weeds and minimise damage to native or other desirable plants. However, this method is labour intensive and best suited for small, scattered plants.
Herbicide options
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 9907 Expires 31/03/2030
Fluroxypyr 200 g/L
(Various products)
Rate: 500 mL to 1 L per 100 L water
Comments: Spot spray
Withholding period: Do not graze failed crops and treated pastures or cut for stock feed for 7 days after application. See label for further information.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
PERMIT 9907 Expires 31/03/2030
Fluroxypyr 333 g/L
(Starane™ Advanced)
Rate: 300 to 600 mL per 100 L water
Comments: Spot spray
Withholding period: Do not graze failed crops and treated pastures or cut for stock food for 7 days after application. See label for more information.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
PERMIT 9907 Expires 31/03/2030
Glyphosate 360 g/L
(Various products)
Rate: One part product to 50 parts water
Comments: Spot spray
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate
PERMIT 9907 Expires 31/03/2030
Glyphosate 360 g/L
(Various products)
Rate: One part product to 9 parts water
Comments: Splatter gun
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate
PERMIT 9907 Expires 31/03/2030
Glyphosate 360 g/L
(Various products)
Rate: One part product to 20 parts water
Comments: Wipe onto leaves
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate
PERMIT 9907 Expires 31/03/2030
Metsulfuron-methyl 600 g/kg
(Various products)
Rate: 10 - 20 g per 100 L water plus surfactant
Comments: Spot spray
Withholding period: Nil (recommended not to graze for 7 days before treatment and for 7 days after treatment to allow adequate chemical uptake in target weeds).
Herbicide group: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors)
Resistance risk: High
PERMIT 9907 Expires 31/03/2030
Metsulfuron-methyl 600 g/kg
(Various products)
Rate: 10 g per 1 L of water plus surfactant
Comments: Wipe onto leaves
Withholding period: Nil (recommended not to graze for 7 days before treatment and for 7 days after treatment to allow adequate chemical uptake in target weeds).
Herbicide group: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors)
Resistance risk: High
Biosecurity duty
The content provided here is for information purposes only and is taken from the NSW 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. |
Reviewed 2026
