Brachychiton acerifolius (Illawarra Flame Tree)

February 27, 2007

Featured tree

Origin: Disjunct populations are found from the Cape York Peninsula southwards to the Shoalhaven region of New South Wales, but the greatest concentration of the population is in the dryer areas of the Illawarra Range.

Habit: Typically 10-15m x 8-10m

Description: Semi-deciduous, maple-like foliage and fantastic flower display of masses of bright scarlet flowers that come out just before Christmas. These flowers are frequently followed by long follicle fruits.

Tolerances: Succeeds in many conditions

Notes: The fruits don’t seem to have the itchy character found with B. populneus.

Root space: Based on mature size tree would require approximately 47m3 root volume (Crown projection method).

Availability: Common.

Reference: Spencer, R. 1997, Horticultural flora of south-eastern Australia, Volume 2, University of New South Wales Press.

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23 Responses to “Brachychiton acerifolius (Illawarra Flame Tree)”

  1. Robert Says:

    The photo you have of Brachychiton acerifolius in flower was taken by ME!! You have taken the image from my web site, please remove it from yours.

  2. Petrina Says:

    Dear Agnes,

    Thank you for your query.

    With a clearance of 5.5m between the pool and the tree, the targeted removal of one or several large roots at 5.5m from the tree base should be tolerated by the tree, and such root removal is not expected to affect tree stability.

    Removal of half the root system is not expected to be tolerated by the tree and, as one of the functions of tree roots is to provide anchorage, such root removal could jeopardize tree stability making your tree susceptible to failure at ground level.

    Until such time as it can be established thorough direct evidence that roots from the adjacent Illawarra Flame Tree are contributing to the cracking, any root removal would be premature, and possibly unnecessary. Should roots be contributing and significant root removal is required, I suggest you engage the service of a local arborist to provide advice on appropriate management options.

    Kind regards,

    James Martens-Mullaly

  3. Agnes Si Says:

    About 1 1/2 metres away from the side of my house is an established flame tree of about 15 metres high. It gives us visual beauty and vibrant bird activities. Its canopy shades and secludes our top floor living room.

    My house sits on an inclined terraced block of land. The flame tree is about 5 1/2 metres away from my in-ground pool. This pool built about 20 years ago sits half into rock and the other half supported by concrete. There is a crack in my pool. If my outstretched arms represent the length of the pool face-on, then the crack is along the middle of the pool’s width. The gape of the crack is wider at the side that sits on rock and is less than 1/2 cm wide. The crack tapers into a hairline towards the middle and up again to the other side.

    A structural engineer comes out next week to check the integrity of the pool’s support structure. I am quite sure the flame tree’s root system will be questioned as to the extent it might be undermining the subterranean solidity of the pool.

    Obviously I want to preserve both the flame tree and the pool. PLease tell me if I can sever this half of the root system to protect both. I appreciate your expertise and experience.


  4. James Martens-Mullaly Says:

    Thanks for your query. The Illawarra Flame Tree is deciduous in spring or the tropical dry season and flowers just before the new leaves appear in early summer, though the timing can fluctuate from year to year, and locale to locale. It seems unusual that you mention dead flowers as the Illawarra Flame Tree typically flowers later in the year.
    A simple test to check for branch vitality is as follows: if the outer bark of small branches, say the width of your middle finger is scratched using light to moderate fingernail pressure to remove the outer bark and reveals green beneath then the branch is alive. If scratching reveals a brown colour or discoloured / dark staining then the branch is likely to be dead. If you are still unsure that the branch is dead, take a sample to your local nursery for confirmation. A dead branch however does not mean the entire tree is dead. If you are still concerned I suggest you engage an arborist to inspect your tree.
    While poisoning can cause sudden death, sudden death can also result from natural causes, i.e. extended periods of flooding / soil water logging, disease or pest attack.
    Here’s hoping your tree is not dead!

  5. WILLY LEAHY Says:

    Willy L Says: September 13,2011 at 12.30pm HI everyone, I have a question, I have a beautifull Flame tree approx 20m, don’t know age approx 25 yrs,. 2 months ago lost all leaves, flowers, and branches are breaking, it looks dead, why would this be happening, do you think its been poisened? how can I tell. Please help. Willy

  6. Stephen Frank
    Stephen Frank Says:

    Andrew, I am not aware of the Illawarra Flame Trees reputation for failures (root plate or branch). In my experience I have not seen this species causing such problems in the urban landscape. I have certainly seen some specimens develop acute branch attachments that could be problematic over time, but have not seen these trees shed any limbs. However, all trees are individuals pending genetic makeup and also tend to grow under different growing conditions, which could impact their safety and viability. I would recommend you have the tree assessed by an arborist in your area to allay any concerns.
    Thanks for your query.

  7. Andrew M Says:

    Hi everyone – I have an approx 20m high Illawarra Flame tree in my front yard. It is a beautiful tree and is an important part of the local streetscape. I was hoping for some opinion/experience in relation to the tree’s strength during high winds. It is located only about 4 metres from our house and the direction of the prevailing wind means that if it fell, it would take out my baby’s room :(

    I really don’t want it to be cut down – but I really hate windy days ever since the baby came. The tree is quite tall, but fairly compact in terms of branch spread – probably only 6m across at the most where the longest branches are at the base. I have hugged the tree in really high wind and it moves a bit at the base, but not much.

    Have you had any experience of the Flame Trees coming down in high wind? I guess given its size it has been there a long time (the house is 40 years old, the tree would be about the same) – so maybe they are strong and its compact size would probably also help too.

    Thanks for your help.


  8. Richard Phillips Says:

    Something else to look for with this tree species is the Kurrajong Star Psyllid (Protyora sterculiae). It exudes a clear sticky substance mostly associated with summer stress. It can get so that the area under the tree becomes sticky and gooey.
    We recorded the first known occurrence of this pest in Victoria a couple of years ago at the Parkville campus of the University of Melbourne and although it is still not listed, you can be sure that it is around.

  9. james martens-mullaly Says:

    Hi Martine,

    Trees exude sap in response to tissue damage, which can be caused by a range of factors. Causes of damage commonly include impact from an object (vehicle, whipper snipper, etc), the activity of insects (boring insects), mammals or birds (eating /damaging bark), or the effect of disease.

    I assume the sap you describe is ‘oozing’ from isolated sites on the trunk and branches, though do not know of any specific causes of sap exudation from the Illawara Flame Tree. You mentioned two additional observations; the dry hot weather and a no flowering last summer. Dry and hot weather could result in a water deficiency (drought stress). Drought stress can cause dieback, which reduces plant vigour and increases susceptibility to pest and disease. A lack of flowering in combination with the sap exudation implies reduced vigour, though why the reduced vigour, remains unknown.

    To find answers I suggest you econsider engaging the services of a local arborist to undertake a site visit and inspection as they will be able to interpret the site and tree conditions better than can be acheived remotely.

    Best wishes with your investigations,


  10. Martine Says:

    Dear Sir,

    My Illawarra Flame Tree in the past 3-4 months has been oozing out alot of gluey clear sap. I live in the hills of Perth in Western Australia and we have had alot of dry hot weather throughout last summer, but it has been interspersed with a few wet days in April. Our seasons are a little late in W.A. The tree did not bloom last summer like it did in 2009.


  11. James Martens-Mullaly Says:

    Hi Jacques,

    The appearance of the Brachychiton acerifolius as you describe is not unusual for the species. Flowering only accompanies leaf fall, and as some trees are not fully deciduous, the result can be patches of foliage and patches of flowers throughout the canopy, or one sided as you describe.

    The blops of clear substance are likely to be sap that has exuded from broken branches or wound sites on branches in the canopy.

    That the tree has continued flowering and retained leaves are alive implies normal plant functioning and tolerance of the recent inundation.


  12. Jacques Says:

    We have an Illawarra Flame Tree, more than 10 years old. It is blooming now end Feb begin March living in Ipswich Qld. The strange thing is only half, one side has leaves, the other side has only flowers. The flowery side doesn’t look too healthy. Under the flowery side on the ground are blops of a clear substance. What could be the problem? In the floods the tree roots were under water for a couple of days.


  13. Ken Says:

    Thanks for help ringtail possums were
    the problem
    merry xmas
    regards Ken Stockton

  14. Ken Says:

    Dear David
    Thank you for the information. I shall put a guard around today.I cannot see any scratch marks on trunk re possums. Process of elimination. whatever is eating it starts from the outside of the leaves like a cutting caterpillar and just leaving a skeleton

  15. David Balsamo Says:


    It sounds like possums to me. Look for scratch marks on the lower trunk and the size of the ‘bite’ mark on the damaged leaves.

    Cheers and all the Best

    David B

  16. David Balsamo Says:

    Thanks Jim for the post. Please refer to Stephen Frank’s comments earlier in this blog. I think you will find them most helpful. You may also want to spike the soil before you irrigate just to make sure that the soil is not already damp. The planting distances sound very close.

    Cheers and all the Best

    David B

  17. jim nichols Says:

    I have three Brachychiton acerifolius (ii?)growing in a triangle, about 2 metres apart in a clay soil which has poor drainage. These trees never grow any higher, but have bushed out a wee bit. I water them for an hour each week.
    Am I over-watering them? I live south-west of Cairns in the cooler country of the Atherton Tablelands.
    Ironically, an extremely healthy flame tree looks brilliant in full flower right now, opposite my place (over the road) in the yard of a house that’s not been occupied for over two years. That tree is never artifically watered and, further, we are in one of the biggest droughts this place has ever seen in modern times.
    Any comments would be appreciated.

  18. Ken Says:

    I live on the Mornington Peninsula Vic and have an Illawarra Flame Tree (9 years old) that is being attacked at night time. I think it could a beetle of some type. I check it everyday and cant see any pests at all. I have sprayed it religiously this year and put vaseline around the butt. This has slowed down the damage on new and old leaves but is not eliminating the pest. Can you help?
    Regards Ken

  19. James Martens-Mullaly Says:

    Hi Alison,
    I would be interested to see a picture of the insect and affected trees if possible – Pls send to

    Has the gully experienced waterlogged soils, extended periods of inundation. If so then root dieback may have occurred resulting in the observed tip dieback, though I would expect all parts of the affected trees to show signs.

  20. Alison Says:

    We have several flame trees in Brisbane and most are suffering fro what looks like a borer attack – ie same look as tip moth on red cedars. It’s pretty severe on most despite, or because of(?), a good rainy year. The tree least affected is on the top of a ridge, poor soil very dry; the worst affected have lovely rich red gully soil. All have plenty of sun.

  21. Steve Andrew Says:

    Brachychiton species can be attacked by a pest such as the Kurrajong Leaf Tyer. Will group a cluster of leaves and tie them together. I have seen borers affect new growth and tips will die back. But I haven’t seen the new growth just eaten.
    My suggestion is to note when the new growth is occuring and treat with a systemic insecticide. Confidor is the safest suggestion,drenching the root zone with product, but if the growth remains affected then dimethoate would do the job. Be careful.
    Ungrafted trees can take time to flower. Be patient.

  22. Stephen Frank
    Stephen Frank Says:

    Brachychiton acerifolius likes to grow in deep, well drained loam, in a sunny position with at least some degree of summer (or summer-autumn) rainfall. The Illawarra Flame Tree is deciduous in spring or the tropical dry season and flowers just before the new leaves appear in early summer. The tree is tolerant of temperate climates.
    Specimens do not tend to flower until they are older (research suggests this can vary from 6-20 years).

    The tree can be variable from year to year in terms of its deciduous extent and flowering. A specimen may flower only partially. This could be as a result of the proceeding pervading climatic conditions.

    I am not aware of specific pests that may infest this species. I would suggest you trap one of the pests and take it to the local nursery for identification and control options.

  23. Claire Kembrey Says:

    We have an Illawarra Flame Tree which is about 4 or 5 years old. It has never flowered and all the new growth seems to get attacked by something….

    Please any ideas as to why its not flowering and what we can do to prevent it from being eaten…?

    Kind regards

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