Thursday, May 5, 2011

Kurrajong - The Perfect Shade Tree

Brachychiton populneus
Family: STERCULIACEAE
Kurrajongs are dry rainforest trees which take the “dry” more literally than most. We see them far out on the western plans, as in this specimen in a Western Downs town which is doing such a good job of shading a cool Queensland-style house.

Their deep roots help them survive droughts. Deep roots also mean (as with other dry rainforest trees) they are less likely to create problems for buildings and other structures. However the roots do seek water, so should not be planted closer than 3.5m to water pipes or sewage lines.


Another part of the secret of kurrajongs’ drought survival is the capacity to drop their leaves in dry winters. The degree of leaf drop depends heavily on the availability of soil moisture, so in wet winters they may lose very few of them. This photo was taken near Toowoomba in June 2008, which was probably the driest of all the dry times in our recent long drought.




The species can grow tall, as shown in this bushland example, also near Toowoomba. Usually, rainforest species only grow this shape if surrounded by other trees. It is possible that this very old tree spent its youth in a quite different environment from the grassy eucalypt woodland you can see in this modern photo. A great deal of such country, along the Great Dividing Range and the valleys to the west of it, was once dry rainforest. It was cleared so long ago that we have forgotten it was ever there. The shape of this tree may indicate that this was the case here.


Kurrajongs have a very pretty flower, and unlike some of the other Brachychiton species (notably the flame tree Brachychiton acerifolius), they don’t link flowering with leaflessness.
This photo was taken in October, and the tree had a shady green canopy.
While mature trees can put out a great show of flowers, it won’t happen every year, so the kurrajong’s ornamental qualities are largely based on its cool green canopy.


As with many Australian trees, their juvenile leaves differ from the leaves on older trees. These leaves are from a very young tree.









The shape on the right is the one we most commonly see, while the one on the left only occurs on mature trees.








I photographed this paddock of kurrajongs at Gilgandra. They were neatly pruned, and I wondered why. Then we drove on to visit the Dubbo Western Plains Zoo, where we watched giraffes being fed with kurrajong leaves. No doubt this explained the mystery!

The photo is such a good demonstration of the results that we can get from pruning most of our dry rainforest tree species. You can see how well these Australian native trees would grace a formal garden. They can be kept to a size suitable for the suburbs, and make very good street trees, as seen in Goondiwindi.




This young kurrajong in Crows Nest is being groomed for the job.









Pastoralists have long recognised the value of kurrajong leaves as emergency drought fodder for their stock. Unfortunately they have all too often solved their problem by cutting down whole trees, a curiously short-sighted solution. The result is that, while we see many young trees in the Toowoomba district, large, old ones are rare.


Kurrajongs are host trees for one of our larger butterflies, the tailed emperor (Polyura pyrrhus sempronius). We caught this delightful pair “kissing” in the bushes at Kwiambul National Park last weekend. (Butterflies kiss with their antennae.)


Brachychitons are recognised as being fire resistant. A row of them on a fenceline downhill from the house, in bushfire-prone areas, could make all the difference (though of course no tree will resist a very large bushfire). A green canopy catches sparks, and might just be the factor that saves a house from catching alight.
A “home among the kurrajongs” is a very Australian image, and considerably safer than the one among the gum trees which is celebrated in the well-known song.
Kurrajongs can be transplanted at up to 8 years old.

PROPAGATING KURRAJONGS
I have done quite a bit of this, and regard it as a pig of a job.If you are going to handle the seeds, you need to wear gloves because of the tiny irritating prickles on the seed coats.
So I was delighted to receive the following suggestions from a reader, Rob, from Canowindra:
I have just started to grow more from seed as we have had rain. My method is to scrape the seeds from the pods, when ripe, with a screwdriver. Place seeds in a capped jar with a couple of pebbles and shake vigorously to remove husks. Flushing the jar with water will remove husks and then just dry the seed in the sun for storage. To germinate, I put mine in a jar and pour RAPIDLY boiling water over them. I then place them in a folded, moistened kitchen paper and place in a zip lock sandwich bag. Last group was ten seeds and all germinated. Presto, in a couple of days roots appear and they are ready to pot. Keep the water up to seedlings in our area and the growth is phenomenal. I’m sure God smiled when he gave us Kurrajongs! "
Thank you Rob. I have only used hot water from the tap. We do have a very hot solar hot water system, but I am interested to hear how well your seeds respond to the boiling water.
I feel sure this method would also work for bottle trees. I would be a bit more cautious about the very hot water for Brachychitons that come from scrub or rainforest habitats where fire is not part of the ecology.
Rob also says that Kurrajongs are recommended as a suitable species for Bonsai, so if you have no room in your garden, you could grow some for this purpose, or just as attractive pot plants.

67 comments:

Stan Lusby said...

Thanks for the info. I witnessed Kurrajong in the drought of 1966. I had only been in the country for five weeks as a young immigrant surveyor and wondered then why they were not used in swathes as fire retardant protection for human settlements against the eucalypt killer fires like you have in NSW at the moment.

"Ignorance is not lack of knowledge but the mischievous desire to ignore."

Stan Lusby
Hsven Street
Moeraki
South Island NZ

Patricia Gardner said...

Hi Stan.
I am interested to hear your point of view. This is certainly a tree that performs well in the drought.
We do see Brachychitons used as minor firebreaks far more than you would have seen in here in 1966.
The problem with them is that they are not useful, in enough other ways, for it to be regarded as financially viable to sacrifice the amount of land that would be needed for firebreaks on a scale would have any effect on the kind of fire they're having in NSW at present. A hot fire in Eucalyptus country can jump many kilometres through the air to another stand of eucalypts. One would need great, long belts of kurrajongs many kilometres wide - not really a practical proposition.
A nice thought, though.
Cheers,
Trish

Anonymous said...

Hi Trish
I am planning to grow kurrajongs as an ember catch break around our house in the Adelaide Hills. Can the kurrajong tolerate frosts?
Thanks in advance.
Jules

Patricia Gardner said...

Hi Jules.
They are said to be able to tolerate frosts to at least -5°C.
do you know how cold your frosts are?
If you haven't already done it, next winter you might like to leave a maximum-minimum thermometer outside overnight in winter, in selected places (on a stake so it sits a few inches above the ground).
there are always quite wide variations in the temperatures around any given site, depending on the degree of slope and the amount of shelter. It is likely even to include some frost-free spots. Knowing your frosts can be a useful tool in choosing the right plants for the right places.
Of course another way of discovering whether a plant is likely to survive in your area is to find out if it grows naturally there. Choose a site with similar slope, aspect and degree of shelter, and Bob's your uncle!
Here's hooping Kurrajongs work for you!
Cheers,
Trish

margy.gill said...

We have a currajong in our front yard and love it. One problem is it drops a huge amount of sap which sometimes looks like rain and is very sticky. I assume it is because of the lack of rain. Is there anything we can do about it?

Patricia Gardner said...

Hi Margy.
Nice to hear from you.
I'm afraid I can't offer you any instant solution for the sap problem, which is not one I have come across, with kurrajongs.
Sticky sap is usually a sign of plant damage. Are you able to track down where it is coming from?
Is it an old tree?
Trish

Anne E said...

Hi, just had many ladies to my garden for a monthly garden club meeting. Many said the name of my unknown tree was a Kurrajong tree. However after reading and looking at google entries I'm not so sure. The tree has 3 prongs like the pictures, but it certainly doesn't tower. Do you think it could still be a Kurrajong?
Anne O'Brien
Toowoomba

Patricia Gardner said...

Hi Anne,
Kurrajongs don't necessarily "tower". The street trees in Goondiwindi are quite small, despite apparently being old. The problem with tree height is that tree size varies with the soil and available water, but especially according to what is growing around them. They stretch tall if they need to compete with other trees for light, but stay low, broad and compact if they're getting plenty of sunshine. Kurrajongs (like bottle trees) are particular prone to this variability.
I find internet statements about the height of trees sometimes irritating. The writers seem to want to boast that they've found another even taller one, which was probably in a gully in a forest somewhere, stretching to match the canopy on the nearby hillside. The height may even have been a historic record, from the days when Australia had rather more in the way of forests and old trees.
The same plant in a garden might be a happy, healthy tree which reaches its maximum at a third or even a quarter of the claimed height. These extreme height descriptions do put people off planting them in their gardens, which is a pity. If we're growing a plant in a garden, we don't want to know the record height. We want to know what it's likely to do in a garden.
Better understandings of the likely height of garden plants come from plants which have grown in the open since they were tiny, such as those in streets, parks, and gardens.
The first photo in my article shows a huge tree in a garden in Millmerran. I have only ever seen another one of similar size that I could be reasonably sure was a planted specimen. (It is in the Helidon State School grounds) I suspect it would take 100 years or so to reach this kind of size.
The other characteristic which helps identify kurrajongs is the rather soft wood. As with bottle trees and flame trees, they sound a bit hollow if you knock on the trunk. It hardly even counts as timber, being the kind of thing cattle can eat. You wouldn't want children to climb any of these trees, as the branches would break fairly easily.
Hope this helps.
Trish

Robyn Bird said...

How long does it take a Kurrajong Tree to mature?
I'm really interested to plant more because I like the comment about them being fire resistant. i live on a bush block in a fire prone area.

Patricia Gardner said...

Hi Robyn.
The question is difficult to answer, as like so many "dry rainforest" type trees, kurrajongs are capable of being slow to the point of seeming to hibernate, or quite fast, depending on conditions.
For fast growth, they need to be kept moist in the root zone, (meaning the soil deeper than about 15 centimetres). The less water you waste on the surface, where most will be lost to evaporation, the better.
The soil moisture levels in much of the local region are perfect for planting right now, after the good rain. And to plant while the weather is still quite hot gives the little plants a reasonably long first growing season before winter sets in.
In drier times I have had excellent results from burying a large plastic bottle with a hole in the bottom beside each of my small trees, and filling them with water as often as possible for their first season. This wasn't with kurrajongs but with another dry rainforest species, but I think the effect would be much the same.
It's important to keep grass well away from all young trees, of course, and a layer of mulch both helps keep soil moisture in, and encourages healthy soil fungi which can make all the difference to young trees.
I think kurrajongs are a great choice for fire-prone areas. All species of dry rainforest-type trees are pretty good for this, too, so they're the sort of thing to look at if you want some variety.
Eucalypts and pine trees are the high fire risk plants, so are best avoided where fires might be a problem.
Cheers,
Trish

Anonymous said...

Hi Trish. I live in Mackay, Qld. I have two Poinciana's which unfortunately have to be removed due to root systems causing damage to the house so I am looking for a shade tree to replace them. Would the brachychiton populneus grow well here do uou think? And is the root systen invasive? Thanks, Toni

Patricia Gardner said...

Hi Toni.
I suspect kurrajongs wouldn't be very happy in your coastal climate. I can't remember seeing them when I was up there, and I think it would be too damp for them.
There are a lot of lovely shade trees native to your local area, which might suit your purposes better. I think you could probably get some good ideas and advice from the rather wonderful botanic garden you have there in Mackay.
There are also some very good books on tropical gardening. such as "Across the Top. Gardening with Australian plants in the tropics" by Keith Townsend, and others. You could try the shop at the botanic gardens, and maybe bookstores in town, for them.
Hope you find something wonderful to grow.
Cheers,
Trish

Tim Allen said...

Hi thanks for all this great info . I live on the coast the soil type is sand and ph level is 8.0 , do you think a
Kurrajong would be suitable ? . many thanks.

Patricia Gardner said...

Hi Tim,
The pH shouldn't be a problem, but the sandy soil might, and kurrajongs might also dislike the humidity of a coastal climate. This is a plant that likes its air dry.
There's nothing to stop you giving it a go, but it may be a long-term disappointment.
I am a person who loves to see plants growing in their own place in the world, where they participate actively in the web of life we call "the ecology". I would suggest that you think of exploring your local native flora for something else that might suit you better.
Australians are often surprised at just how rich their local plant diversity can be, once they start investigating. The result, should you choose this option, is a plant which loves to grow at your place. Robust good health always makes a plant more beautiful, and as a bonus, you get a plant that isn't an ecological "passenger".
Cheers,
Trish

Ed said...

I live in Tucson,AZ USA and the local nurseries here are selling these. I bought 10 of them that were already 5 years old. I've noticed on one of them that the leaves are a little wilty. I'm suspecting it's from lack of water. As soon as they were planted I watered them with drip emitters with 24 gallons of water each day for a week. Then I taperered off to every other day. 9 of them are doing great, but one of them is larger and showing wilty leaves. I'm watering that one every day still to see if that's the reason.

Patricia Gardner said...

Nice to hear from you, Ed
Are these plants in pots?
As you would have gathered from my blog, my experience is with growing them in their own native range, and of course we only grow them in the ground,where they flourish through our worst droughts. I have never seen them grown in pots.They have a large tuberous root, and I can't imagine that they would take very happily to long term pot culture. Deformed roots might make them prone to disease.
They would also hate to be overwatered, and could suffer from fungal diseases as a result.
However, it sounds as though yours are soldiering on despite their less than optimal conditions. Long may they continue!
Cheers,
Trish

Carolyn said...

My trees are planted with grass surrounding them. I am trying to water my grass and not over water the trees. The trees are losing leafs at a rapid rate and I think this is not good. Please help me!

Thanks,

Carolyn

Patricia Gardner said...

Hello Carolyn,
You don't say where in the world you are, so although you are writing in June I have no idea whether you are in early winter (southern hemisphere) or early summer (northern Hemisphere)
It is normal for kurrajongs to drop their leaves in early summer.
They don't do it every year, and sometimes the leaf-drop is only partial. Sometimes it is more complete. It usually means that the tree is going to flower (something they also don't do every year). If the flowers are pollinated, they will then produce seeds, which you can grow, to make more trees. If you do this, check the roots as they grow to make sure they have enough room in the pot. Kurrajong seedlings have a large tap-root like a fat carrot, and need plenty of room for it.
You can also eat the seeds (lightly roasted) or make a coffee-like drink with them, but make sure that you rub the seeds well (with gloves on) to get rid of their hairy little coats. Those little hairs are prickly and will leave tiny prickles in your mouth!
Don't worry that you might be over-watering the ground your tree, unless your soil is rather soggy or swampy. Kurrajongs are very tolerant, and happy to be given some water if the soil drains well, especially when they are making new leaf after a leaf-drop.
Let me know how it goes after a few months.
Cheers,
Trish

Unknown said...

Interesting posts here! My question is about getting potted plants to survive. I picked some seeds from pods on the ground 2½ years ago in Morocco and successfully planted them back home in Stockholm, Sweden. Only today did I get them clearly identified as Brachychiton populneus. I am grateful for this explanation of the remarkable difference in leaf shape juvenile/mature. Now: I will keep them as indoor plants, obviously, for as long as they want to cooperate, but I have to cut them down before they hit the ceiling. And the stems are so thin! Can they be cut radically? Will they survive? Will they branch out?

Patricia Gardner said...

Hello Finn.
Good to hear from you!
I am astonished at where these plants turn up! Morocco and Sweden!
As you would have understood, my blog is really intended for people in my part of Australia, who are interested in growing their own locally native plants. I have never heard of Kurrajong being grown as indoor plants. I am not surprised that they are long and thin. I am probably not as surprised as your little kurrajongs, though, which must be astonished to find themselves growing indoors in Sweden! Such a very different place from their native country.
This is not a tree that anyone usually wants to cut at all, but I have seen them pruned near Dubbo. They were being cut to feed their leaves to Giraffes at the zoo. They seemed to like it well enough, and grew into a trees with dense rounded canopies.
I would suggest you give them a try.You have nothing to lose!
Best of luck with them.
Trish

Barb said...

Hello Finn, I have a small, self seeded, Kurrajong which is growing 10 feet away from my house. I am encouraging it to grow as it will provide lovely shade for our porch which faces north west. My husband is worried about the roots? I have always thought Kurrajongs had a large tap-root, so I thought would be ok planted near paths and the porch? Is this wishful thinking on my part?
We average about 12 inches of rain per year and I water my garden regularly. Many of our street trees are Kurrajongs but a lot of people here curse them because they can be messy. I love them. Can you tell me if I will have a problem with the roots?
Thanks in advance,
Barb.

Patricia Gardner said...

Hello Barb.
Sorry for the slow reply. No comments are published on this site until I (as the owner of the blog) have had a look at them and decided whether to publish them. It keeps away the peculiar people, and those who want to use my comment section for advertising etc.
People who badly want an answer to a question tend to email me at the contact address given, rather than to ask through a comment.It does get a quicker response than waiting for me to look up my "comments awaiting moderation".
Because this is a personal blog, rather than a forum, it is not a particularly suitable way to have a conversation with another comment writer, either. Finn is very welcome to reply, of course, if he happens to read your comment.
With regard to your query, you will notice that I have advised in the body of the blog that kurrajongs should not be planted closer than 3.5 metres from water pipes or sewage lines. Because these items carry water, they are more prone to attack by the roots of living trees than are house foundations or paths.
I may have been being overcautious when recommending 3.5 metres. Brachychitons generally have a bad reputation in this regard, but they are not all the same, of course. Kurrajongs, being a dry-country cousin of most of the other Brachychitons, are likely to have deeper, less spreading roots. I notice that the Western Water site (a peri-Melbourne water authority) considers kurrajongs acceptable within 2 metres of sewer lines (and that they are the only brachychitons it recommends for planting that close).
So at 10 feet away, you can probably be confident that your kurrajong won't pose a threat to your porch foundations.
You might like to confirm this, for your husband's peace of mind, by doing an internet search on "sewer pipes" and "kurrajong".
Cheers,
Trish Gardner

Barb said...

Hi Patricia,thanks for your reply. I must explain, I wrote to you twice because I was sure I lost this first post. I must have been having a bad day. I also apologize for getting names mixed up. I realize now, I used Finn's name instead of yours. Silly old me!
Thanks so much for your advise regarding my little Kurrajong. We have just had some wonderful summer rain and more little leaves are appearing. Thanks again, much appreciated.
Barb :)

Patricia Gardner said...

Hello again Barb.
Having taken my own advice, and looked up what various regional water authorities and local councils recommend in the way of planting distance away from sewer pipes, I began to wonder whether I had given good advice at all in suggesting that you do an internet search! I was astounded at the lack of consistency between the recommendations. One site (Western Water, a water authority near Melbourne) thinks that a kurrajong (Brachychiton populneus) can be safely planted 2m from a sewer line. Another recommends you keep it more than 6 metres away, and yet another recommends more than 10 metres. Presumably the writers all claim to be experts, or they wouldn't be writing things like that for local governments and water authorities, but you really have to wonder how much some of them really know!
After a bit more trawling, I began to wonder whether whether some of the people who compiled the lists even knew what the plants on their lists were, let alone what their root systems are like. Their distance groupings were such an odd hotch-potch. The same distance recommendations are made for plants on a list that includes of water-hungry species that should obviously be kept away from pipes, trees with a broad, shallow root-reach that would interfere with foundations and footpaths, and small-rooted drought hardy things that are hardly likely to be a problem at all. I got the impression that some of these people would prefer to have no plants in our suburbs at all. Our pipes would be VERY safe, but would be be having any fun?!
One of the sites that impressed me as having been written by someone who knew what he/she was talking about was http://www.egwater.vic.gov.au/wp-content/uploads/2016/03/PlantThoughtfully2013.pdf
It didn't refer to kurrajongs,though. The only Brachychiton it mentions is Brachychiton acerifolius (Flame tree). They recommend keeping it 4 metres from sewer pipes. Flame trees are less drought hardy, and have higher water needs than kurrajongs (Brachychiton populneus, and by inference you could plant the latter closer than 4 metres to a sewer pipe, and closer still to foundations.
The final decision is yours and your husband's, though.
Trish

Patricia Gardner said...

Hi Barb.
A lot of people write double comments. There is something horrible about having taken the trouble to write, and have it disappear into the blue, isn't it. I have explained the process in the fine print somewhere, but it's easy to overlook.
As you will see, your comment gave me a great deal to think about, and I posted another blog on the subject of tree roots and built structures, and mentioned your query. More reliable information is definitely needed.
It will be interesting to see whether it pulls out any responses.
Trish

Jenny S said...

Hi Trish, I have a beautiful old Kurrajong on the acreage we just bought. This year it dropped its leaves, flowered and we now have hundreds of seed pods weighing the branches down lol. I would love to grow more of these trees from these seeds and want to be sure I do it right as I don't have naturally green fingers!
It is mid summer here (Far S Coast of NSW), do I wait for the seed pods to drop or do I collect? Do I take the seeds out of the pod straight away or do I wait until I am ready to plant them. When is the best time for me to plant them. If I'm not planting now how do I best store them? Could I get a big garden bed and plant them all together or do I need a separate pot for each? Whern is the best time of year and age of plant for transplanting?
Thank you in advance. Jenny :)

Patricia Gardner said...

Hello Jenny.
Lucky you, to have such a lovely tree.
It won't set a seed crop as good as that every year, so do take advantage of it.
Your question is such a good one that I really should do a blog on the answer. I will do it when I get hold of some suitable photos, but meanwhile, here's a rather full answer for you:
You will know when the seeds are ready for picking from the tree, as they will look dry and split open.
Look after yourself when getting the seeds out of the pods. It's worth splurging on a pair of cheap gloves (the kind you use for washing up) to protect your hands from the irritating hairs on the skins of the seeds. It's best to do this job as soon as possible, as the seeds are very nutritious and seeds left in their pods are often discovered by insects or mice, and eaten.
The next step is to husk the seeds, which should also be done ASAP to help keep them safe from grubs which might be concealed under the husks. This is done by rubbing the seeds between your (gloved)hands. The husks usually rub off quite off easily, but if it doesn't seems to be working, leave them to dry in the sun for a few days first. Once you've got most of the husks off, you can tip the mixture of seed and husks from bowl to bowl in a breeze. This winnowing process lets the husks blow away and you are left with clean seed, ready for planting or storage. Kurrajong seed keeps for many years if very dry. Storing it in the bottom of the fridge works, but it also keeps well at room temperature - inside the protection of a sealed container.
However, like most seeds, kurrajongs germinate best if fresh. Germination is improved by soaking them in hot water (from the tap, not boiling) overnight and planting them next day. You could get seedlings in as little as 7 days. Older seed might take 35 days.
You can grow them in a well-dug, well-watered garden bed, or in biggish pots full of seed-raising mix. Start checking the roots soon after the seedlings appear, as they grow more quickly than you would think from the amount of leaf. If you have them in a garden, an old dinner knife is a good tool for easing them up gently without damaging the roots. Once the roots are 3 or 4 centimetres long, it's time to move them.
You can pot them on, or better still move them to their permanent positions at once if it is somewhere they can be taken care of till established. The trees which grow best and live longest, are always those with the best roots. Getting them into their permanent positions very young is the way to achieve this.
If you do pot them on, use good deep pots because Brachychitons need plenty of deep root-room. Even then, they should still go into the ground when very young, as once the roots hit the bottom of the pot and turn a corner, the process of pot-binding begins, and the roots will never be as good again. Don't wait till the little trees look pretty above the ground. (Many pretty nursery-bought plants are disappointing in the long run. By the time they are judged old enough for sale - i.e. they are "nursery-pretty" - the roots are often well past their best. Hence the too-common belief that Australian plants are "short-lived".)
The best kind of "pot" for tree seedlings is the sort called forestry super-tubes. These are as close to bottomless as a pot can be, without actually letting the potting mix fall out. They should be kept off the ground and top-watered, so that the roots go straight to the bottom and get air-pruned. Unlike seedlings in pots, those in tubes can be kept for as much as a year before planting out. Forestry tubes are designed so that they can get full of root without pot-binding. ("Pot-binding" doesn't mean pots well-filled with roots. It means that the roots have turned corners.)
They can be planted out at most times of year, provided they won't dry out, or suffer from frost.
Hope this helps.
Cheers,
Trish



Jim said...

Hi Good Info on here !
I have 4 Kurrajongs in Geraldton West australia planted 2 months ago from 90litre pots there now about 3m high i think they grew nearly 300mm in the first 2 months . 2 in backyard well drained sandy soil look very healthy .
2 in front lawn where soil is heavy and clay like (I know its not ideal)
have dropped all leaves on the bottom half of tree although top still looks healthy . Is there anything i can do to save these two or will they not grow in this type of soil?
cheers Jim

Patricia Gardner said...

Hello Jim,
Thanks for your comment.
It raises an interesting point. Kurrajongs are regarded as an environmental weed in Western Australia, and are considered harmful to the environment. They are native only in the east of Australia, but do tend to "naturalise" over there, spreading outwards from gardens where they have been planted.
It does make the point that Australian native plants can become weeds, just like garden escapees from overseas (such as pepperinas and Athel trees or tamarisks) when they are planted away from their native range. Western Australia has suffered from it, more than most places in Australia.
(Australia is not just a big bucket, with "native" plants sloshing about in it freely. They all have their own places, in their own ecosystems. The statement which I sometimes hear, that something is a "native", therefore cannot be a weed by definition, is one that shows the speaker's naivety!)
These interlopers displace the genuinely native trees, because they grow more vigorously away from their own natural pests and diseases. The knock-on result is that your own native animals have increased difficulty finding food and habitat.
So you might choose to remove all your kurrajongs.
I've been there, done that, with weeds planted in my days of innocence of environmental matters. I know the feeling of pain it gives, to remove a perfectly healthy plant!
But believe me that you will be glad of it in the long run, especially if you choose West Australian natives to replace it. You will notice the increase in birds, butterflies etc, and come to be pleased that you made the hard decision.
Western Australia has large numbers of the world's most special, unique plants, and a major threats to them is invasion by plants from Eastern Australia which have gone feral.
Sorry to put a damper on your pleasure in your little kurrajongs, but what can I do, except give an honest answer?
All the best.
Trish

Jenny C said...

Hi.
We live in Algarve (S.Portugal). In our garden we had a mystery tree which I have now identified as a Kurrajong..(thanks to you brilliant and interesting blogspot).
It is beautiful,gives good shade and flowers well.. especially at the moment..we are in early summer temperatures about 30c.
Our problem is when to prune the tree...it has already started to show signs of leaf drop even though there are still flowers on it. The tree is about 10ft tall and beloved by sparrows!
Very many thanks...I am going to try to grow more if I get some pics this year.
Jenny C

Patricia Gardner said...

Hi Jenny.
Nice to hear from you.
About pruning, I would find it difficult to give you really good advice, as these trees are rarely pruned here in Australia. You can see from the photo of the trees where leaves were being collected to feed giraffes at a zoo, that they were happy to be pruned and developed very dense canopies, However none of the other trees in the blog would have ever been pruned.
Unlike European trees, kurrajongs sometimes drop their leaves opnce a year, and sometimes don't. They are most likely to drop their leaves if they are having a good year for flowering, which doesn't happen every year. Leaf drop occurs in early summer when they are flowering, so it is not unusual for them to be losing their leaves now,in the northern hemisphere. Some of our Australian brachychiton trees are at their most beautiful when they are flowering heavily but have no leaves at all. They will grow their canopy back in time for the hottest summer weather.
First, are you sure you want to prune your tree? It doesn't really need it.
Second, if you do decide to prune, to get a smaller, denser canopy, then it probably doesn't matter much when you do it. I would suggest you wait until they have finished flowering. If you want the seeds, you could wait until after that, too. It's up to you!
cheers,
Trish

Unknown said...

Hello,
Just looking at the information on Kurrajongs and noted that you thought the trees in the paddock at Gilgandra had been trimmed to be straight across the bottom... and perhaps the leaves fed tot he giraffes at Western Plains Zoo. This is not the case. You will notice in all paddocks where there are Kurrajongs and livestock have been grazed that the trees are all trimmed to the height that a sheep and/or cow can reach. They tend to also be lopped (some of the top branched trimmed and felled to the ground) during dry times for stock feed.

Patricia Gardner said...

Thanks for the comment Tracy.
I am familiar with the neat trimmed canopy bottoms that result from a number of our native dry rainforest species being live-stock-trimmed from below. It was the all-over lopping that fascinated me.It did seem to have been done by someone who was carefully managing the plants to keep up a continuous supply of leaves.
It could indeed, as you say, be the case that the trees in my photo had been lopped for livestock other than giraffes. However, the fact that we watched the giraffes being fed with kurrajong leaves the day after I took the photo still leaves me with the suspicion that the landowner had a sideline in supplying edible edible leaves to the zoo.
So (unless, of course you have personal knowledge of that particular paddock) I regard the jury as still out on that one.
The result is certainly picturesque, and a lesson for us that our native trees often respond very well to skilled pruning.
Trish

Julia Mitchell said...

Hi Trish how are you ? We have moved to Moree and have beautiful tree but it looks like maybe wood grubs have got to it. It’s a huge tree and near our house. We aren’t an expert but it looks bad and perhaps we will have to get rid of the tree. Any advice would be great thanks

BN said...

Hello,

Thanks for the informative blog.

We actually have this tree (Brachychiton Populneus) in our backyard in Las Vegas USA :)
Our weather is similar to the low humidity weather in Australia.

The tree is about 4-5 years old and has grown to 15-18 feet tall
but has not branched out at all. It just shoots up straight.

I was wondering if this would branch out later (after x years)
as the main purpose of our tree is to provide shade.

Thanks for any information.

Patricia Gardner said...

My apologies for the slow publication of your comment, and my slow response. I have been away from home and without access to my comments file, so am just catching up on the backlog now.
Hmm. Feet. We Australians have operated with metres for so long that we lose the ability to convert to the old imperial measurements in our heads. Everyone in my generation had to learn it, but one rarely needs it here now.
I think that must be something like 4.5 to 5.5 metres.
This is not unusual for a Brachychiton of any species that has been grown with other plants or buildings around it, so it reaches up to search for light. Could that be your problem? I would expect it to branch eventually for you, but you might like to consider supplementary under-planting to help the shade production process along. Waiting for a tree to provide the shade you want can be a slow process.
Wishing you all the best.
Trish

Linda said...

4 years late, but I know what they are talking about. It comes from the actual pods. Gooey stuff. We have a lot of them around Central West NSW doing it at the moment. The pods on the ground are oozing this sap. I'm currently googling to see if it has a use like sweet food or bush medicine or even glue.

Patricia Gardner said...

Hi Linda.
Thanks for your comment about the kurrajong resin.
My attempt to find anything on the internet has drawn a blank. The only thing I found was a reference to a botanical specimen of Brachychiton gregorii resin, from which I have inferred tentatively that the "gooey stuff" on the kurrajongs is a resin, not a gum or a kino. It is usually the gums rather than the resins that are edible. Plant resins tended to be used for glue.
Please do let me know if you find out anything more.
Trish

Patricia Gardner said...

Now I've found another one. A quote from a foruun in which the writer, on the subject of Prachychiton populneus, wrote "McBryde (1978:246) provided historical records from nthn NSW which indicate use of resin and bark fibre for hafting of hatchet heads to handles."

Unknown said...

Stumbled on this great blog. We have two Brachychiton Populneus trees that were planted in August 2017 from 24" boxes (.6 m) in Southern California. They have been doing very well until recently. One tree had profuse blossoms, the other had none. About July 1st we had very high temperatures, 114 degrees F, 45 degrees C. Now the tree that had profuse blossoms is losing all its leaves, the other is losing many of its leaves. They get a decent amount of water, I have taken to giving them 4 gallons, 15 liters of water twice a week with a slight bit of fertilizer.
Should I be worried?

Patricia Gardner said...

Hello California.
45.5 degrees celcius. The kurrajong should cope with that.
I see I omitted to mention in my blog post that all brachychitons have a tendency to be partially deciduous in summer. It doesn't happen every year, and usually only starts to happen after a tree has gained some age. It is usually followed by a good flowering.
However, my advice is to hold the water and the fertilizer. You could be killing it!
This is a tree that likes it tough. It would be hard to kill it with heat, drought, or poor soil. Water and/or fertiliser might do it, though.
Trish

Unknown said...

Thank you. My babies are now on a water diet and wil not get fertilizer either.

Patricia Gardner said...

Best wishes for success!
Trish

Judy said...

Hi Patricia, we have recently built a home on a cleared block of land on the escarpment in Toowoomba. I have recently noticed a number of trees regrowing which I have been told are Kurrajong. Do Kurrajong grow from old roots? Also these plants are multi stemmed so am unsure how their shape will end up. Just makes me wonder if they are indeed a brachychition despite the oak shaped leaf. Would appreciate your thoughts. Thanks Judy

Patricia Gardner said...

Hi Judy
I don't know of kurrajong regrowing from old roots, but everything is possible!
I am unsure exactly what you mean by an "oak-shaped" leaf. The photos on the blog show most of the possible variations. Do your plants look like any of these?
Kurrajong is a very likely plant to be growing naturally on your escarpment block, so perhaps this is what you have.
Maybe you could email me some photos? My email address is in the right-hand column of the blog near the top - unless you are using a phone, in which case you need to scroll to the bottom of the screen and click on "View web version".
Cheers,
Trish

Judy said...

Thanks for your reply Trish. Have emailed you a couple of photos. Hope they help
Judy

KM said...

We bought our beautiful kurrajong “Natasha” At about 2m height, almost 20 years later she stands proudly at about 7-8m and has always grown well in our Brisbane front yard. She hosts beautiful jewel bugs every year and gets lots of comments from people passing by. Natasha typically loses her leaves every summer (partial loss only) but quickly replenishes with beautiful soft green leaves. It is now July and ALL of her leaves have fallen off along with many branches. I’m worried for her health. She has had a few trunk cracks over the past 18-24months which the local nursery told us to cover with paint to prevent insect attack. Any suggestions of what may be wrong would be appreciated.
Kathryn

KM said...

We have a beautiful Kurrajong “Natasha” in our front yard in Brisbane. We planted her at about 1.8m height almost 20 years ago and she has flourished and is frequently the receiver of compliments particularly when she is dressed up in her Christmas baubles, or is host to jewel bugs.
She loses her leaves each year but as they are dropping there is always evidence of the new growth coming through. A week or so ago she started to lose her leaves but it has been far more rapid and rude spread than any previous year with almost the whole tree turning completely broken and small and larger branches breaking off. Typically her leaves would bronze not turn completely brown and dead like this year. I’m so worried about her, she is a much treasured tree. Any advice would be very welcomed.
I have a photo but an unsure of how to attach as Ive never blogged before

Patricia Gardner said...

HI KM.
Apologies for my slow response. I have been away, and managing my blog without a big screen in more that my simply knowledge of technology can cope with.
I'm sorry to hear that "Natasha" is looking sickly. Frankly, it doesn't sound good!
While it is true that kurrajongs do sometimes have a very complete leaf drop, it doesn't usually happen in July, as you say.
I can offer you no help, I am sorry, except to wait and see.
If you lose her, there is really nothing to do except plant something else in the space. You might like to try a different species, though. If your kurrajong has disease, there may still be "germs" in the soil which could attack another kurrajong or one of its Brachychiton relatives.
I hope it has indeed turned out well for you by now, though.
Trish

DAVE HART said...

Hi Patricia,
Dave here. We are living on a small property about 10 mins outside Castlemaine in the central Goldfields of Victoria. We have a beautiful, very large Kurrajong tree, which must be over a hunderd years old. I'm told it was planted by one of the sons of the Archer family who originally inhabited our little Miner's cottage, before he went off to the First World War. It is considered something of a War Memorial in the dirstrict, since the story goes, that although he managed to survive the war and return, Robert lost his site due to shrapnel damage, and he used to return home to the family house and hug this Kurrajong to 'see' how much it had grown. This tree has been featured in articles written and published on llocal War memorials, hence we feel we are charged with a great duty to care for her and ensure her health and continued flourishing.

She is very beautiful and offers fabulous shade for our cottage, however, this year she has lost nearly all her leaves beginning in early December. She has partiallly flowererd before, but never lost her leaves in this manner in the five years since we have been here. I am seeing small sprays green like shoots on many, but not all of the branches though. A few have this small green bulb on the end. I'm hoping you will tell me this is normal and suggests flowering is about to occur, but I'm worried. The thought of losing her to distress, whilst in our charge, is simply unimaginable. If you think there might be a problem, your advice would be very welcome...I'll do anything I can to help her survive!, including regular watering if required...Please help...Regards Dave

Patricia Gardner said...

Hi Dave.
What a precious thing you have on your property!
I have two comments about the leaf drop.
The first is that it has been a very hard year, and many Brachychitons up here are being slow to recover from their usual spring / early summer leaf drop. We've just had some very good rain, so I expect ours up here to rebound well, now. Yours may do the same.
The second is that trees die of old age. This is an often overlooked cause of tree death! Many of the famous War Memorial (WW1) bottle trees planted in the Roma Streets have died in the last decade, and I would expect kurrajongs to have about the same lifespan. Trees in the wild might live longer, but trees that someone has planted can be relatively short-lived. Trees planted outside their own native range are also likely to be less long-lived. I am uncertain whether kurrajong's natural range extends as far south as Castlemaine.
If you feel any doubts about the survival of your tree, I suggest you collect up what historical data and photos you can to make sure they are properly preserved, and plant a new tree if you think that a replacement would be better than no kurrajong at all. this is important if your tree does recover but continues to look poorly, which can be a sign that it's getting elderly. If your tree seeds this year you might like to grow a seed of the parent tree. If it does survive, what you will achieve in the long term is another lovely tree and another cahpeter in your heritage tree's story.
Wishing you all the best.
Trish

Steve Murden said...

Hi Trish,
I now live in Tamworth NSW and have two lovely Kurrajongs in my yard. One is about 20 years old and only 4me high and has been struggling along for a while with leaf loss, but now the leaves are 'curling' (as you find on citrus trees) and getting a black tip where the leaf seems to have died. This is now also happening to its neighbour who is 32 years old, 8me high and a very healthy tree with flowering and abundant seed pods. The younger tree had borers which I trimmed the branches to remove a couple of years ago and the tree thrived for a while but is now sickly looking and bare. They both are putting out new leaves (after the wonderful rains) but this leaf curl has me worried.
To answer one of the previous writers, the 'sticky goo' coming from the seed pods is the trees natural defence against insect attack of the pods, which would make them sterile.
We had hundreds of Kurrajongs growing in the paddocks and hill country of our farm (towards Gunnedah) and I cannot count how many I lopped for the cattle during the dry spells over the years. They are an amazing tree and the most useful for a farm.
Thank you for taking the time to read this and I hope you may be able to use your knowledge to suggest anything I might do to help these trees of mine.
Yours,
Steve.

Patricia Gardner said...

Hello Steve.
It's nice to hear from someone who has used these trees for stock. Living proof that native trees have a place to play in a modern economy!
I agree that the leaf curl doesn't sound good. It is probably caused by an insect. A healthy tree will cope with a fair bit of insect use, but sometimes a bad season (or something that causes the tree roots to be unhealthy, like damage or poor drainage) will make it vulnerable. Here in Toowoomba the Brachychitons all lost their leaves for an unusually long time this summer, but have picked up again with the rain.
I hope you have had some it. A good season may help your trees to recover.
Cheers,
Trish

Anonymous said...

Hi Trish. I’m a long time Kurrajong affectionardo in an area where they are common. In one of our paddocks we had some growing out of an elevated solid, rocky limestone knob. I would have thought then to be 100 + years old. Unfortunately in this 3 year dry spell a couple have died, which I found upsetting and blame climate change. Next, I note that you have mentioned that you hadn’t heard much of them being grown indoors in pots. I think you will find that the species is listed as suitable for bonsai. I have just started to grow more from seed as we have had rain. My method is to scrape the seeds from the pods, when ripe, with a screwdriver. Place seeds in a capped jar with a couple of pebbles and shake vigorously to remove husks. Flushing the jar with water will remove husks and then just dry the seed in the sun for storage. To germinate, I put mine in a jar and pour RAPIDLY boiling water over them. I then place them in a folded, moistened kitchen paper and place in a zip lock sandwich bag. Last group was ten seeds and all germinated. Presto, in a couple of days roots appear and they are ready to pot. Keep the water up to seedlings in our area and the growth is phenomenal. I’m sure God smiled when he gave us Kurrajongs!
Rob.
Canowindra NSW.

Patricia Gardner said...

Hi Rob.
What a fabulous idea for cleaning the seed ready for planting, and for germinating the seed. Thank you for sharing it. Please see above, I will add your suggestion to the blog.
Trish
PS I agree about God smiling. I think He smiles quite a lot when He looks at plants.

Unknown said...

We have a wonderful old kurrajong on our farm and can confirm that cattle love is stronger shade and also chew out the low hanging leaves in dry times. My question is how to estimate how old the tree is ?

Patricia Gardner said...

Yes, they are beautiful trees.
Estimating the age of Australian trees is very difficult. We Australians tend to have been brought up on the "rule" used in northern hemisphere climates where there is a long, well-defined winter each year. That means an annual period of no growth followed by a period of strong growth - an annual growth ring. All they have to do is count the rings.
Here, our trees might make almost no growth some years so there is no obvious ring, and then might make several growth rings in other years if there are a couple of separate good periods of rain.
However, one thing we know about kurrajongs is that cattle love to eat the young ones. Depending on where your tree is, you might be able to have a good guess at its age. there is a strong probability that at the time cattle were first brought to your piece of land, it would have been too tall for cattle to eat the canopy off and kill it. Depending on fast they grow in your area, that would put it at ten to twenty years old or more. (Of course it could already have been a hundred years old. Who would know?)
You have something precious there.
Cheers.
Trish

Julia said...

Hi I have a beautiful old Kurrajong in my garden. At the moment it has nothing growing under it. I have left the lower branches to 'droop' and the area under the tree is quite shaded at all times of the day. Do you have any suggestions for what I could grow as ground cover under it? Thanks for your site and thanks in anticipation of an answer :-). Julia

Patricia Gardner said...

Hi Julia.
That is always a difficult question to answer without knowing where you are (and what kind of nurseries you would be using)and how much water the area under the tree is likely to get. You need to keep in mind that kurrajongs do not naturally grow in well-watered areas, or have heavy shade underneath them. The things that would grow under a Kurrajong in nature would be plants that depend on getting quite a bit of sun, and are as drought hardy as the kurrajong itself. Too much water could damage your tree, as can too heavy a mulch (by keeping the soil more damp than kurrajongs really like), so you need to be careful that your idea of planting under the tree doesn't result in killing what sounds like a beautiful plant.
Answers to some other questions would help me give you a better answer.
So the first question is whether you really want to plant it out, or could you find other uses for that bit of open space, such as a nice garden seat.
The second is whether you want to stick to natives.
The third is whether you are thinking about low ground covers, big shrubs, or something in between.
I suggest you decide these things, then go and browse in nurseries to see what is available and appeals to your taste.
If you would like to discuss it further, can I suggest you email me (address in column to the right)? It is easier to converse that way than to wait until I get around to looking at comments, which might only happen every few weeks.
Trish

Unknown said...

Hi, we have kurrajong trees on our property and one has died from grubs and now another looks sickly. Do you know if you can treat the tree to save it?

Patricia Gardner said...

There are commercially available poisons to kill grubs, of course, but you might do better to look at the cause of the problem.
Native plants, growing naturally, don't usually get infested with grubs unless something else is making them weak or unhealthy. Have there been any changes that would affect the roots? Building or soil disturbance close to the trees? Introduction of livestock? Extra water, fertiliser, or herbicides? Treatment of the sickly tree could mean looking after the plant's root zone a bit more carefully.
Have there been other changes, such as removing surrounding vegetation, leaving it more exposed? Changes to the groundwater levels?
Another cause of sickliness is old age, of course. A tree on the downhill run will often get infested with pests of one kind or another, and the best course can be to plant a new one, rather than spend time and money trying to revive the old one. Nursing a sickly plant which is never really going to be good again is a depressing thing to be doing, when you could be nurturing a new generation of trees.
Hope this helps.
Trish

Cheryl O said...

We have a kurrajong which I think is over 15 years old. We live in Cabarlah Qld and since winter it has dropped all it's leaves. New growth is happening along some branches but it never seems to develop full leaf. The tree is covered in lycen and I fear it may be dying. Any advice you can give would be most welcome. I can send you a photo if you like

Patricia Gardner said...

Hi.
Trees do die of old age, but yours doesn't sound like an old tree. It may just be having a little rest, which trees just do, sometimes. It is possible that all this rain has given it a bit of a shock and it is resting until it gets over it. They are not a tree that likes soggy ground.
It is worth just checking that the root zone is in good health, though. Trees often die because we humans have built something too close to them or otherwise changed the root conditions. Kurrajongs are pretty good at coping with this, though.
The lichen shouldn't be a problem. A good lichen population is a sign of clean air, so is something to feel good about. You don't see lichen in cities, or where there is heavy traffic. Lichen doesn't damage trees.
Meanwhile, it could be worth planting up a few more trees, if you are not already doing this. We humans like old trees so much that we sometimes forget that there does need to be a new generation coming on.
Cheers,
Trish

dianna said...

My kurrajong is sick 6 m tall on edhe of a 1.2 m embankment probably planted in 1930's a few metres from house

it lost its leves in winter its temperate climate was not as cold as usual rarely hitting a frost. but wet and we have had almost double normal years rainfall. its not flowered this year normally glorious
its just got an attempt of reshooting leaves young ones. no bugs sap suckers etc effecting it. a neibours row of same age also looks sick. can we treat it with anything ? do anything. being on embankment tgat soil is at least free draining its on a ridge but its been super wet

Patricia Gardner said...

Hi Diana.
You give me no hint as to whether you are in Australia, or which part of it. The internet is a world-wide thing, and where an enquiry comes from does affect my response.
If you are fairly local (as in not too far from Toowoomba), then yes, the weather is probably the cause of your tree's unusual behaviour. This year's climate has caused all the Brachychiton species to behave abnormally. Flowering has generally been late, and many trees have skipped flowering altogether. I think they were also affected by the very long winter, even though there was little actual frost, and by the unusual amount of winter rain. Wet feet can cause Brachychitons to die, but it sounds as though yours is in a situation where it would recover well.
However, I see no reason to think your tree is actually sick. These are very adaptable plants, and they have spent many thousand of years adapting to survive in Australia's extremely variable climate.
It is also part of kurrajongs' typical behaviour to have a complete leaf-drop now and then, with these incidents often being many years apart, but sometimes recurring in few close years. They are usually over it by about November, but this is an unusual year.
I am interested that you say it is "normally" glorious with flower. It is actually rather unusual for a kurrajong to flower well every year. They have years when they flower with enthusiasm, and years when they seem to be saying "Nope, not in the mood". so if you have had a few years of heavy flowering you can expect your tree to take a rest for a few years.
So no, I would suggest that you don't upset your tree by trying to treat it with anything. The most likely scenario is that it will recover in its own good time.
Good luck.
Trish

Anonymous said...

Red meat ants actually farm the tree for sap * so in turn the tree produces even more 🐜 🌳

Patricia Gardner said...

Interesting comment.
I would be interested to hear a bit more from you on this. Perhaps you could email me? Do you have photos of the meat ants harvesting sap? I believe they are keen on sugar, so if they eat it, it is probably sweet.
The reason I ask I that I actually wonder whether the ants are directly using the sap, or whether they are actually farming caterpillars on the kurrajong, so they can milk their sweet sap. Meat ants (Iridomyrmex species) are known for caterpillar farming. They bring the caterpillars out from their nests at night to graze on the leaves, so you don't see it happening in the daytime. However the ants can be very defensive of "their" tree, which you do notice.
The common pencilled-blue butterfly (Candalides absimilis) breeds on kurrajong, and needs an ant helper, which I understand to be an Iridimyrmex species - probably your common meat ant - to care for its babies. There are probably other small butterfly species as well, so these are worth looking out for though not now, in winter. If you see them hanging around the kurrajong, they could well be looking for a good ant-rich tree to lay their eggs.
Maybe they supplement this diet with sap in winter when the butterflies aren't breeding?
Trish