Yellow bells (Tecoma stans)

Also known as: yellow trumpet bush , yellow trumpet flowers, yellow bignonia, tecoma

Yellow bells is a shrub or small tree with clusters of bright yellow flowers and beanlike pods. Plants can form dense infestations that reduce habitat for native animals.

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How does this weed affect you?

Yellow bells is an environmental and agricultural weed that:

• competes with native plants
• reduces habitat for native animals
• outcompetes pasture plants, reducing grazing productivity
• forms dense stands, restricting movement for people, native animals, livestock and machinery
• competes with fruit trees in orchards.

What does it look like?

Yellow bells is a large shrub or much-branched small tree usually growing 3-8 m tall, rarely to 10 m tall.

Leaves are:

• 8–25 cm long
• divided into 3-13 leaflets (usually 3–7)
• leaflets are:
  • oval shaped with a pointed tip
  • 2.5–10 cm long and 8–30 mm wide
  • bright green on top, paler underneath
  • serrated along the edges
  • hairless
  • in opposite pairs with a single (terminal) leaflet at the tip.

Flowers are:

• bright yellow with feint reddish lines in the throat
• tubular with 5 rounded lobes
• 3–5 cm long and up to 3 cm wide
• in clusters of up to 20 flowers at or near the stem tips
• fragrant
• mostly present in spring to summer, though sometimes all year.

Fruit are:

• slightly flattened bean-like pods with many seeds
• initially green, turning brown when ripe
• 10–30 cm long and 0.5–2 cm wide.

Seeds are:

• oblong-oval shaped with a white-transparent wing at each end
• flat and papery
• up to 2.2 cm long and 0.6 mm wide (including wings).

Stems are:

• green and smooth when young
• light brown to pale grey and grooved when mature
• spotted with small pale lenticels.

The trunks can be up to 25 cm in diameter.

Similar looking plants

Yellow bells looks like:

• golden trumpet vine (Allamanda cathartica), which is a garden plant. It does not have serrated leaves and has larger flowers than yellow bells (up to 15 cm). Its fruit are rounded prickly capsules.
• shrubby allamanda (Allamanda schottii), which is also a garden plant. It doesn’t have serrated leaves and its fruit are rounded prickly capsules.
• yellow oleander (Cascabela thevetia), which is a weed with similar flowers, but the leaves are long and thin and not serrated. It has fleshy fruit.

Where is it found?

In NSW, most yellow bells infestations are in the North Coast, Hunter and Greater Sydney regions. A few plants have also been found in the Northern Tablelands.

It is native to tropical America and the West Indies.

Yellow bells was introduced into Australia as an ornamental plant and first naturalised near Roma in Queensland in 1973.

What type of environment does it grow in?

Yellow bells grows best in sunny conditions in sub-tropical and tropical climates with 700–1800 mm annual rainfall. Plants are drought tolerant but do not tolerate frosts. They prefer light, well-drained soils and are salt tolerant. 

Yellow bells grows in:

• riparian areas including mangrove habitats
• edges of rainforest and eucalypt forest
• open woodlands and grasslands
• sand dunes
• pastures and orchards
• disturbed areas such as roadsides.

Maps and records

• Recorded presence of Yellow bells during property inspections (Map: Biosecurity Information System - Weeds, 2017-2026)
  These records are made by authorised officers during property inspections under the Biosecurity Act 2015. Officers record the presence of priority weeds in their council area and provide this to the NSW Department of Primary Industries. Records reflect the presence of the weed on the date of inspection.
  
  

How does it spread?

By seed

Yellow bells starts producing seeds within two years. Each seed pod can produce up to 77 seeds, though on average they produce 42 seeds. Seeds can remain viable for up to 4 years if conditions are dry.

The seeds are spread:

• mostly by wind
• in moving water, including sea water
• in contaminated soil
• by people dumping garden waste. 

By plant parts

Yellow bells plants produce suckers, especially if damaged. New plants can grow from fragments in dumped garden waste.

References

CABI ( (2019). Datasheet: Tecoma stans (yellow bells). Retrieved 1 October 2024 from: https://www.cabidigitallibrary.org/doi/10.1079/cabicompendium.52951

Gilman, E. F., & Watson, D. G. (1994). Tecoma stans yellow elder. Fact Sheet ST-625. Washington, DC: Forest Service, Department of Agriculture of USA. Retrieved 8 October 2024 from: https://www.researchgate.net/profile/Dennis-Watson-2/publication/239553149_Tecoma_stans_Yellow-Elder1/links/54c652e30cf219bbe4f82685/Tecoma-stans-Yellow-Elder1.pdf

Identic Pty. Ltd. & Lucid. (2016). Weeds of Australia Fact Sheet: Tecoma stans (L.) Kunth. Retrieved 1 October 2024 from: https://keyserver.lucidcentral.org/weeds/data/media/Html/tecoma_stans.htm

Pelton, John (1964) "A Survey of the Ecology of Tecoma stans," Butler University Botanical Studies: Vol. 14, Article 11

PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 1 October from: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Tecoma~stans

More information

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Control

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. Check treated sites regularly for regrowth or new seedlings.

Prevention

Ensure that pastures are not overgrazed. Plant and maintain dense pastures to compete with seedlings. Rehabilitate disturbed natural areas by planting appropriate native species, including ground covers if possible.

Physical removal

By hand

Hand pull or dig out seedlings and small plants. Remove all of the taproot to avoid regrowth.

Machinery

Larger plants can be pulled out by machinery but follow up will be required as cut roots can regrow.

Chemical control

Spraying

This method is suitable for seedlings and smaller plants. Spray actively growing plants. Cover all of the foliage evenly with the herbicide.

Basal barking

Basal barking can be used for plants with stems up to 5 cm in diameter at the base. Spray the bark all the way around the stem from ground level to 30 cm high. Wet thoroughly to the point of runoff. Apply to dry stems as wet stems can repel the mixture. 

Cut stump method

Herbicide mix: Cut trunks or stems less than 15 cm above the ground. Apply herbicide to the cut and the sides of the stump immediately.

Gel herbicide: Cut stems horizontally preferably no higher than 10 cm above the ground. Apply a 3–5 mm layer of gel for stems less than 20 mm in diameter and 5 mm layer on stems more than 20 mm in diameter.

Stem inject

Do not ringbark the tree when using this method.

Gel herbicide: Use an axe or saw to make horizontal cuts 5-20 mm deep into the sapwood around the trunk of each tree. Space the cuts evenly, no more than a 2- 4 cm gap between them. Apply a 5 mm layer of gel over the lower surface of each cut.

Herbicide mix: Drill holes or make cuts (with an axe or saw) through the bark into the sapwood tissue in the trunk. Drill holes should be a maximum of 5 cm apart and cuts a maximum of 3 cm apart. The holes or cuts should be all the way around the trunk of the tree. Apply the herbicide within 15 seconds of drilling the hole or cutting the trunk.

Herbicide options

See Using herbicides for more information.

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PERMIT 9907 Expires 31/03/2030
Glyphosate 360 g/L (Various products)
Rate: 1.0 L in 50 L of water
Comments: Spray seedlings.
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate

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PERMIT 9907 Expires 31/03/2030
Glyphosate 360 g/L (Various products)
Rate: 1 part per 1.5 parts of water
Comments: Stem injection or cut stem application.
Withholding period: Nil.
Herbicide group: 9 (previously group M), Inhibition of 5-enolpyruvyl shikimate-3 phosphate synthase (EPSP inhibition)
Resistance risk: Moderate

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Picloram 44.7 g/L + Aminopyralid 4.47 g/L (Vigilant II ®)
Rate: Undiluted
Comments: Cut stump application. Apply a 3–5 mm layer of gel onto stems less than 2 cm diameter. Apply 5 mm layer on stems above 2 cm diameter.
Withholding period: Nil.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate

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Triclopyr 240 g/L + Picloram 120 g/L (Access™ )
Rate: 1.0 L in 60 L of diesel (or biodiesel such as Biosafe).
Comments: Basal bark application for plants with stems up to 5 cm diameter at the base. Cut stump application for plants with a diameter up to or more than 5 cm at the base. Some root suckering may occur. See label for information about using biodiesel.
Withholding period: Nil
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate

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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.
Hunter	Regional Recommended Measure* (for Regional Priority - Asset Protection) Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value.
North Coast Exclusion (eradication) zone: Clarence Valley LGA, Lord Howe Island, Port Macquarie-Hastings LGA. Core infestation (containment) zone: Ballina Shire LGA, Bellingen Shire LGA, Byron Shire LGA, Coffs Harbour City LGA, Kempsey Shire LGA, Kyogle Shire LGA, Lismore City LGA, Nambucca Valley LGA, Richmond Valley LGA, Tweed Shire LGA.	Regional Recommended Measure* (for Regional Priority - Containment) Whole of region: Land managers should mitigate the risk of the plant being introduced to their land. A person should not buy, sell, move, carry or release the plant into the environment. Exclusion zone: Notify local control authority if found. Land managers should eradicate the plant from the land and keep the land free of the plant. Core infestation: Land managers should mitigate spread of the plant from their land. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value.
North West	Regional Recommended Measure* (for Regional Priority - Eradication) Land managers should mitigate the risk of the plant being introduced to their land. Land managers should eradicate the plant from the land and keep the land free of the plant. A person should not deal with the plant, where dealings include but are not limited to buying, selling, growing, moving, carrying or releasing the plant. Notify local control authority if found.
Northern Tablelands	Regional Recommended Measure* (for Regional Priority - Asset Protection) Land managers should mitigate the risk of the plant being introduced to their land. Land managers should mitigate spread of the plant from their land. A person should not buy, sell, move, carry or release the plant into the environment. Land managers should reduce the impact of the plant on assets of high economic, environmental and/or social value.
	*To see the Regional Strategic Weeds Management Plans containing demonstrated outcomes that fulfil the general biosecurity duty for this weed click here

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Reviewed 2025