Chinese celtis (Celtis sinensis)

Also known as: celtis, hackberry, Japanese hackberry

Chinese celtis is a large tree that produces thousands of fleshy fruits. It outcompetes native plants especially along waterways on the north coast of NSW.

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How does this weed affect you?

Chinese celtis spreads quickly and can form dense thickets. It

  • outcompetes native trees and shrubs
  • reduces habitat and food for native animals
  • invades disturbed bushland and riparian areas
  • has potential to invade agricultural land.

What does it look like?

Chinese celtis are large trees usually 10-15 m tall (occasionally up to 20 m), with spreading, moderately dense crowns. They are deciduous to semi-deciduous and drop their leaves in late winter to early spring in northern NSW.

Leaves are:

  • 4.5–9.0 cm long and 3.0–4.5 cm wide
  • egg-shaped with a pointed tip
  • bluntly toothed along the edges towards the top of the leaf
  • on stalks 5-6 mm long
  • alternate on the stem.

Flowers are:

  • greenish with 4 petals that are about 2 mm long
  • only present for a short time.

Fruit are:

  • green ripening to orange or red-brown
  • about 7–8 mm long
  • fleshy and contain one seed
  • ripe in autumn and early winter.

Seeds are:

  • white
  • 4 mm in diameter

Trunks

Trunks are smooth with mottled grey bark when mature.

Young stems:

  • have a slight zig-zag appearance, bending at each point where a leaf is attached
  • have small white dots.

Similar looking plants

Chinese celtis looks similar to these introduced species:

  • Nettle tree (Celtis australis), which is pale, almost white on the underside of the leaves and the fruit are brown to black when ripe.
  • Hackberry (Celtis occidentalis), which has grooved bark, purple to black fruit and the leaves are paler on the underside

There are also native plants that look similar:

  • Native silky celtis (Celtis paniculata), which has smooth rather than toothed leaf edges.
  • Native peach (Trema tometosa), which has narrower leaves that are toothed along the entire edge of leaf and generally lighter in colour. Fruit are green, ripening to black.

Where is it found?

In NSW, most established populations of Chinese celtis are in the North Coast and Greater Sydney regions.

It’s native to China, Japan and Korea. Chinese celtis was introduced as an ornamental shade and street tree. It was planted in urban private gardens and public parks.

What type of environment does it grow in?

Chinese celtis grows best in moist areas. Most infestations are in disturbed or previously cleared riparian areas. It prefers clay soils, especially alluvial soils on the banks of waterways and gullies, creek and gullies. It is shade-tolerant.

Maps and records

  • Recorded presence of Chinese celtis during property inspections (Map: Biosecurity Information System - Weeds, 2017-2021)
    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.

  • Estimated distribution of Chinese celtis in NSW (Map: NSW Noxious Weed Local Control Authorities, 2010)
    Map shows weed distribution and density estimated by local council weeds officers in 2010.

How does it spread?

By Seed

Each tree can produce thousands of seeds each year. Birds and flying foxes eat the fruit and spread the seeds in their droppings. Seed are usually only viable for up to two years.

References

Armstrong, T. R., & Keegan, S. L. (1996). Celtis sinensis and its control. In Proceedings of the 11th Australian Weeds Conference, Melbourne, Australia, 30 September-3 October 1996 (pp. 504-505). Weed Science Society of Victoria Inc.

Markus, N., & Hall, L. (2004). Foraging behaviour of the black flying-fox (Pteropus alecto) in the urban landscape of Brisbane, Queensland. Wildlife Research, 31(3), 345-355.

Panetta, F. D. (2001). Seedling emergence and seed longevity of the tree weeds Celtis sinensis and Cinnamomum camphora. Weed Research, 41(1), 83-95.

PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 20 November 2020 from: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Celtis~sinensis

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.

To manage Chinese celtis:

  • control plants as soon as possible so they do not fruit and spread via their seeds
  • look for and control new seedlings after rain
  • check treated areas for several years after controlling mature trees
  • where applicable, establish native plants in control areas to reduce the amount of sunlight, space and nutrients available for new Chinese celtis plants.

Physical removal

By hand

Hand pull seedlings up to 30 cm high. Small isolated plants may be dug out. Cut down larger trees and dig out the stump so that the tree cannot regrow. Be careful not to move fruit and seeds to new areas when removing trees.

Disposal

Contact your local council for advice on how to dispose of the fruit.

Chemical control

Chemical control is most effective when plants are actively growing. Do not spray when the tree is losing leaves going into the winter months.

Spraying

Plants up to 2 m tall can be sprayed. Apply to all leaves of young plants to the point of visible wetness.

Basal barking

This method is suitable for plants with up to a 20 cm diameter trunk. Apply herbicide mixed with diesel all the way around the lower stem of the plant. For multi-stemmed trunks, apply the herbicide from ground level to where trunk branches.

Cut stump method

Cut trunks or stems as close to the ground as possible and apply herbicide to the stump within 15 seconds of cutting. This method works best on plants with a diameter at the base of the tree of 20 cm or less. For larger plants, scrape the cut stem and any above ground roots to expose the layer of the trunk below the bark. Apply herbicide to the scraped areas within 15 seconds.

Stem injection

Drill or make cuts into the sapwood and fill with herbicide within 15 seconds of making the cut.

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.


PERMIT 9907 Expires 31/03/2025
Glyphosate 360 g/L (Various products)
Rate: 1 part glyphosate to 50 parts water
Comments: Spray seedlings and coppice shoots.
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate


PERMIT 9907 Expires 31/03/2025
Glyphosate 360 g/L (Various products)
Rate: 1 part glyphosate to 1.5 parts water
Comments: Cut stump/scrape stem application for saplings. Stem injection application large trees and shrubs.
Withholding period: Nil.
Herbicide group: M, Inhibitors of EPSP synthase
Resistance risk: Moderate


Fluroxypyr 333 g/L (Starane™ Advanced)
Rate: 2.1 L per 100 L of diesel
Comments: Basal bark application, for plants up to 2m high
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: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


Picloram 44.7 g/kg + Aminopyralid 4.47 g/L (Vigilant II ®)
Rate: Undiluted
Comments: Cut stump application: Apply a 3–5 mm layer of gel for stems less than 20 mm. Apply 5 mm layer on stems above 20 mm. Stem inject application for trees: Make a series of cuts 15-20 mm deep around the trunk using an axe or saw. Space cuts evenly with no more than a 20-40 mm gap between them. Apply a 5 mm layer of gel over the lower surface of the cut.
Withholding period: Nil.
Herbicide group: I, Disruptors of plant cell growth (synthetic auxins)
Resistance risk: Moderate


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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.
North Coast
Exclusion zone: whole region excluding the core infestation area of Richmond Valley Council, Ballina Shire Council, Lismore Council, Kyogle Council, Byron Shire Council and Tweed Shire Council
Regional Recommended Measure*
Whole region: The plant or parts of the plant should not be traded, carried, grown or released into the environment. Exclusion zone: The plant should be eradicated from the land and the land kept free of the plant. Land managers should mitigate the risk of the plant being introduced to their land. Core infestation area: Land managers should reduce impacts from the plant on priority assets.
*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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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 2021