Japanese sunflower is a perennial shrub with large yellow flowers. It forms dense thickets that compete with other plants.
Japanese sunflower is an environmental weed in coastal regions of NSW. It
In other countries it is also an agricultural weed. It can contaminate seed and reduce yields in crops such as sorghum and maize.
Japanese sunflower is common on the North Coast of NSW. It also grows in the Hunter and Greater Sydney regions.
It is native to Central America. It is an ornamental plant and has been planted in gardens.
Japanese sunflower grows in tropical, sub-tropical and warm temperate climates, preferring 1000 mm to 2000 mm of rain per year. It can tolerate a wide range of soil types including soils with low fertility. It mostly grows in coastal areas, especially disturbed areas such as along roadsides and railways, embankments, forest edges and creek lines.
Each plant can produce over 120 000 seeds. Seeds are most viable after 4 months of dormancy. The seeds are spread by:
Japanese sunflower can grow from stem fragments. These can be spread by people dumping garden waste.
Japanese sunflower is a robust, perennial, branching shrub that usually grows 1 to 3 m tall but can grow up to 5 m.
Japanese sunflower looks like other weeds when they are not flowering:
Atlas of Living Australia. (2020). Tithonia diversifolia. Retrieved 8 May 2020 from: https://bie.ala.org.au/species/https://id.biodiversity.org.au/node/apni/2900593
CABI. (2020).Tithonia diversifolia (Tithonia). In: Invasive Species Compendium. Wallingford, UK: CAB International. https://www.cabi.org/isc/datasheet/54020#tomeansOfMovementAndDispersal Retrieved 08/05/2020.
Identic Pty Ltd. and Lucid central (2016). Environmental Weeds of Australia Fact sheet: Tithonia diversifolia. Retrieved 22 June 2021 from: https://keyserver.lucidcentral.org/weeds/data/media/Html/tithonia_diversifolia.htm
Miranda, M. A., Varela, R. M., Torres, A., Molinillo, J. M., Gualtieri, S. C., & Macías, F. A. (2015). Phytotoxins from Tithonia diversifolia. Journal of Natural Products, 78(5), 1083-1092.
Muoghalu, J. I., & Chuba, D. K. (2005). Seed germination and reproductive strategies of Tithonia diversifolia (Hemsl.) Gray and Tithonia rotundifolia (PM) Blake. Applied ecology and environmental research, 3(1), 39-46.
PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 22 June 2021 from: http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Tithonia~diversifolia
Successful weed control relies on follow up after the initial efforts. This means looking for and killing regrowth or new seedlings. Using a combination of control methods is usually more successful.
Dig out plants growing in small or isolated patches.
Slash before flowering to prevent seeds from being produced. Follow up control works by digging out plants, continuously slashing, or spot spraying to prevent the plants from reaching maturity.
Spray plants before they flower. Apply herbicide to actively growing plants and ensure that all of the foliage is covered with the herbicide mix.
Cut the stems and apply herbicide to the stump within 15 seconds of cutting.
See Using herbicides for more information.
Metsulfuron-methyl 300 g/kg + Aminopyralid 375 g/kg
(Stingerâ„¢)
Rate: 20 g in 100 L of water ((always add a Wetter 100 mL/100L)
Comments: Spray with a hand gun. Adjuvant: Wetter 1000g/L non-ionic alcohol alkoxylate (TITAN WETTER 1000 or BS1000 or equivalent)
Withholding period: Pastures - Grazing for meat production or cutting for animal feed: Do not graze for 56 days after application. See label for further details
Herbicide group: 2 (previously group B), Inhibition of acetolactate and/or acetohydroxyacid synthase (ALS, AHAS inhibitors) + 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: High/Moderate
Metsulfuron-methyl 600 g/kg
(Various products)
Rate: 10 g in 100 L of water
Comments: Apply to actively growing plants after full leaf expansion but before seed set. Add surfactant.
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
Picloram 100 g/L + Triclopyr 300 g/L + Aminopyralid 8 g/L
(Grazon Extra®)
Rate: 350 mL in 100 L of water
Comments: Apply as foliar spray pre-flowering
Withholding period: Where product is used to control woody weeds in pastures there is a restriction of 12 weeks for use of treated pastures for making hay and silage; using hay or other plant material for compost, mulch or mushroom substrate; or using animal waste from animals grazing on treated pastures for compost, mulching, or spreading on pasture/crops.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Picloram 44.7 g/L + Aminopyralid 4.47 g/L
(Vigilant II ®)
Rate: Undiluted
Comments: Cut stump/stem injection application. Apply a 3–5 mm layer of gel for stems less than 20 mm. Apply 5 mm layer on stems above 20 mm .
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Triclopyr 300 g/L + Picloram 100 g/L
(Various products)
Rate: 350 mL in 100 L of water
Comments: Apply as a foliar spray pre-flowering.
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
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. |
Reviewed 2023