Can anyone identify this tree at all by the leaf and bark. It's tall and deciduous, no thorns, thin flat seed pods. Much like the mythological Lernaean Hydra, every time I cut out a piece of root that's in the way of something it decides to throw up a tree from the root end! It's extensive root system traverses across my whole yard 10+ metres from it's base so it's difficult to avoid encounters with it. The two big trunks are actually the same tree. It has two main trunks coming up from the base plus the bonus thin one in the middle. I'm guessing a previous owner of this place cut a root at the base and it responded with a second trunk.
I should have put something for scale but each of those oblong leaves is about 3cm
The Qld gov weed identifier wasn't much help.
Unhelpfully I can tell you that it is a legume, but you knew that. I've not heard of a legume which suckers though.
The Qld Herbarium still do plant IDs so I believe but whether free these days, I don't know.
It's the suckering that is confusing … suggest Tipuana tipu check with Google Images. The leaves look right (pari-pinnate i.e. in pairs without an odd one at the end of the) size and shape. The flowers will clinch it. There's thousands around Brisbane, they make great street trees, thrive on petrol fumes. They have a single winged seed, unusual for a legume. But many thousands of these seeds per tree so there's plenty of weed potential with Tipuanas. They are from South America originally.
I thought you might be on a winner there Elaine but I just found a couple of sparse pods on the tree up high with my zoom lens and they're flat and different shaped. It's not Easter Cassia (Senna pendula) either which was my first thought as I have one out the front and it flowers and has thin round beans. Maybe it's my complete lack of observation skills but you'd think that I'd remember seeing a sea of flowers straight out from my deck. I may have to pay attention over Spring.
For such a large tree there are almost no pods on the ground but all those leaves are there. Maybe the birds and possums feed on them during winter. They don't so much continually sucker (like the giant Chinese Elm that's doing my head in, but just seem to sprout a new tree from a root whenever I cut the root back from invading a garden bed or hole I'm digging for a new plant/fruit tree.
I also want to check if it has allelopathic tendencies or if lack of growth under/around it is from it's nutrient draw.
Seems like a friend's suggestion of Leucaena ticks all the boxes. The only difference being my bean pods are much smaller, thinner and nowhere near as abundant (thank goodness) than the one's pictured below and the other Leucaena's I've seen strewn around Brisbane. It'll be one of the sub species mentioned in the weed info description.
"This species is a prolific seed producer and it also resprouts after its stems are deliberately cut or otherwise damaged." <---That's the clincher!!!!!!!
And my suspicions are not unfounded. It would seem it contains Mimosine which has negative allelopathic effects on it's surroundings in large amounts with testing being done to see if it's leaf litter extract can be used as a bio-herbicide. :o(
Looks like I'm removing the top layer on the asparagus bed. Fortunately mature leaves have the least amount of Mimosine.
Does it have a white/cream coloured pom pom type flower that are scented when it flowers?? It could be an Albizia sp. - Google image search Albizia macrophylla and see what you think. It's far too big to be leucaena and the pods are quite different.
I can't say I've ever paid attention to it's flowers but it seems like I will looking when next it blooms. Perhaps because they've been so high up (Tree height is ~10-12m) and if the flowers are wispy and white then they wouldn't stand out.
The pods on my tree do look much closer to some of the Google images of Albizia (like the pods and bark of Albizia lebbeck which are almost an exact match). I guess for now I'll wait till it flowers to find out exactly which variety it is. Either way it has the same toxicity/ inhibiting growth effect on neighbouring plants as well as exposed roots shooting up so my problems remain the same. I need to come up with a solution to work around it and be conscious of not putting it's leaves in my compost just in case.
It could be another reason some of the raised beds just never grow anything and why some new fruit tree transplants aren't having a good time in their new position near that tree.
Thanks for the replies. Although I'm not sure I can palm off all my poor gardening skills onto the tree.
I am fascinated to see what it really is! Are you considering living with it? Is it your property or a rental e.g.? If you are going to live with it, the only way that I know of for plants to thrive around a big tree (never mind one who doesn't like company) is to make wicking beds and have all your plants including fruit trees, in big bins or pots secure from invasive roots. Those pods look close to an Albizia sp; I had an A. lebbeck growing in town, pods were longer but flat like that and quite woody when old. Leaflets look similar too. But it didn't sucker or I didn't sever any roots.
The flowers are the only true test of ID supported by the pods and leaflets.
I'm in the process of converting all the raised beds in the back yard into wicking beds as nothing is really growing in them. Most in part because of the slope where any water that goes to the bottom of the raised bed then heads straight downhill. I dug the first one out this week and a massive root from that tree had made it's way into the bed in less than a year obviously loving the watering and manure that was being given to it. That's what got me onto this identification crusade.
If I can I'll try and find a way to work with the tree. I'll trawl the permaculture forums and see what others have done although I have a feeling it's not foreboding well for the tree from my initial investigation. I also want to wait till the neighbours get back from their holiday as it's on the boundary and I always discuss things if it has any bearing on their them.
I'd love a full wicking bed back yard but it somehow defeats the purpose of my permaculture experiment. The wicking beds for now will purely be for nutrient and water intensive vegetables. I've got 15 or so fruit trees that I've planted in the last 2-3 years that seem to be doing okay but they're all well away from this tree except the Nashi :o| which has only been there a under year and has a root from the unknown tree heading towards it already. Being deciduous I've never actually seen any leaves on it bar a few tiny ones at the base that just came up. Fingers crossed for Spring.
It would be costly to have the tree removed but if you want to have in-ground Permaculture as distinct from wicking beds, removal is probably the best option. There are ways of making wicking beds in-ground which might help. There's an awful lot of digging involved (tell me about it ;-) we converted 10 beds) and being on a slope, it's a viable option to swales. Have you been to Colin Austin's website? It's www.waterright.com, he canvasses many options including in-ground beds.
Place something solid under the plastic - corrugated iron e.g. - that could help with roots especially big ones. A sliver of plastic is no defence against roots.