Euc grafting or what?

Sean Freeman

Here's some pics of a Eucalyptus tereticornus down near the river at Nerang Gold Coast..tell me what you think whether you're from Oz or overseas it relates to a number of debates going on here in Oz here and in other forums.

Some questions to get you started...
Whats the cause?? (Any ideas welcome)
Do we think the grafted structure is stronger or weaker and in what ways?
Have any of you seen similar in other trees (not just Eucs) and please post any pics if you have them.

I'll put a couple up here and let you click on the rest.

Treelore

Site history Sean?? any other trees growing beside at another point in time now gone??

Sean Freeman

The site is a small public park squeezed between the Nerang river and the M1, the tree was undoubtedly there before the development of the highway.



To get a better idea of the extent of the development here I have put up a wider shot red dot is the subject tree, the red circle represents an area of relatively untouched riparian buffer that I will visit to get comparative shots of similarly aged trees...I have walked around this area quite a bit there are no other Eucs that have anything like this type of growth in the area to my knowledge.



So sure there would have been far greater numbers of similar sized trees around this one in the buffer before it was developed, and yes the odd growths could be dated tot he period of initial development perhaps....but the very significant grafting in scaffold limbs?

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azrael

Sean ...to clarify ... are you interested in the limb grafting as per pic 4872

OR the burl-like structures as in the other photos

OR BOTH phenomena.

I have seen limb grafting in E.tereticornis too ... see pics below

Sean Freeman

I'm interested nay fascinated in both, how many E. tereticornus have you seen grafting like this? For me the numbers are very very low 2% maybe.

The Nerang river tree seems to be exhibiting a degree of grafting and meristematic cell production beyond anything I've seen on any other tree....or at least without an explaination that I could be comfortable with. Is it just genetics, as Shigo wrote so clearly and emphatically in NTB when comparing resistant individual trees in forest situations. Or is it the result of and external factor....virus bacterium or something else? Until I can dissect one of the protrubences and assess if its origin is in the centre (or there abouts) or more peripherally I'll just be guessing.....what I was hoping clearly forelornly, was that others may have encountered similar oddities and had some musings of their own to share.

My pics don't really do justice to the amount of serious limb grafting going on in this tree, and none of the other trees same species along theis stretch of the river have any grafting at all...let alone the strange scrotum like growths below the limbs!!!!

Treelore

That's kind of what I was getting at with the question of other trees nearby perhaps removed. I meant have there been trees growing right beside that have been removed because the growths look like a partial graft from a neighbouring tree that had grown amongst it's canopy. Could be totally wrong but the pictures suggest some sort of contact with other branches?? I have seen quite a bit of this sort of grafting out towards Eight Mile plains towards beaudesert. Almost defies logic the way masses of timber almost seem to leap across gaps where there was no apparant stem rubbing.

Eric Frei

One other thing Sean, that's also mistletoe haven in that region, maybe has something to play with it.

Maybe something to do with bats or birds, but seldom will you see growth underneath limbs.

Just today I saw a large tereticornis where a limb maybe 10" dia was growing bent down and under, it broke off and looked a little similar to the elephants feet below some of those limbs.

Interesting, keep hunting, the answer is there somewhere.

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Sean Freeman

Eric mistletoe was my first guess and yes there is mistletoe in the tree, it is perhaps possible that this tree has been so compromised internally that it is producing these growths...again I've never seen such things as a result of mistletoe....burls yes but not like these. the dissection will hopefully clear that up one way or another.

Eric Frei

I agree, but look at that pic of how the branch grew underneath, that is extremely odd! I dont think something grew upwards and then formed that nice even collar etc ... nope, that branch grew down, then maybe due to the inverted whacko growth burled or callused etc.

We talk about apical dominance, but what is the opposite and could be possible an extreme hormone imbalance done something.

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Sean Freeman

Yes definately hormones are envolved too...what keeps nagging at me is the placement of these growths what is stimulatng their origin, why here and not 20mm further along? Can't find an explaination that satisfies yet!

azrael

Sean ... In answer to how many .... very few (<1%)...
The one pictured in my post (#4) was the most dramatic I've seen (inspected) with regard to the size of the bridge.

This tree (Forest Red Gum) is now gone ... A TMO consented removal ... & not of my doing.

It was located in a suburban backyard: a remant tree of the former Turpentine/Blackbutt forest in this area (but much less represented in this precinct). I missed one photo in my earlier post....



As to the etiology of the phenomenon in your pics... I have no answers ...

Sean Freeman

Its a good pic Azreal, look I know this is all probably a bit esoteric to many but it fascinates me. just when I really think I'm beginning to get a broad undertanding of tree biology esp Euc biology I get this curve ball!

I will try to get some better closer pics of the grafts and scrotums and hopfully visit other riparian buffer sections along the Nerang river to see if I can find any others (though I don't expect to)

(BTW Azreal hopeful to be working around Southwest Rocks next week...ever done any work there??)

Bernard Keays

Sean.... This is really interesting stuff. I haven't seen anything quiet as weird as this but there are plenty of examples of burls & branch grafts in Euc's down my way. I think Ekka has something with the mistletoe. I haven’t got any other plausible suggestion to make but could it be epicormic growth following a stressful event (storm, fire)? Epicormic shoot gets damaged in another event (invasion by pathogen, insect attack, frost or suncald) leading to a meristematic mass (canker or burl)?

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Bernie

Eric Frei

That's a thought, fire beneath, flames. Hmmm.

It is a good puzzle for sure.

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Sean Freeman

Bernard that would indeed be a very plausable explaination except that these things are still being produced on very small diameter branches higher up in the canopy, I have to think that whatever is triggering their porduction is partly responsible for the ease and degree of branch grafting going on as well, the grafts look like one branch just melted into the other, very much like you'd expect to see in figs, but not Eucs...well not in my experience.

Bernard Keays

Thanks Sean... I'm not suggesting I know what it is but rather offering a suggestion. I'm going to check this tree out at Easter. My better half wants to go to the 'Centenary of Witches Falls' celebration on the Friday 28th of March at Tamborine Mountain. So there might be an opportunity to duck out and have a look at the tree.

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Bernie

azrael

Sean
This article discusses the different grain in burls (called 'wood figures') and it gives some clues about tissue hypertropy and related causes.

Figure in Wood.

Probably need to examine both a cross-sectional piece and long-sectional piece as a start though.

Az

Sean Freeman

Thanks Az I will read through that paper this weekend, its interesting but perhaps not surprising that the wood working perspective is the one that provides greater analysis of burl production.

Also sad to reflect that quite possibly the importation of Elm burls from France did bring Dutch Elm disease to the US.

azrael

Sean ... still fascinated with this thread.
The etiology here is something Ive not thought too much about ... just accepted that its a phenomenon that occurs sometimes ...
Im AM almost positive Ive seen "lesions" like those back when I was kid ... in the trees on the River Flats of the Murrumbidgee River (Wagga/Narrandera).
I'm wondering if there not a relationship with a past flooding regime ... but then I might be right off track ... although I found this 1993 extract (not whole paper).
http://links.jstor.org/sici?sici=000...OR-enlargePage
The trees I saw may have been flooded at a very young age... (see flooding history below)

Sean Freeman

Lenticel hypertrophy is something I'm going to persue..very thought provoking, not the whole story but maybe a big part of it.

playfordtree

Sean, now you know my grasp of tree biology is pretty much zero so please be patient with me.

Forgive me also for derailing your thread a little bit.


Yes indeed those photos are amazing (i've never seen anything like it before either)

My initial juvenile response was to point and say "Look, that trees got hemorrhoids"

Once i had composed myself, my next thought was "Gee, looks like the trees got cancer"
I dont know why i thought that, it just popped into my head.

But it got me thinking, "do trees get cancer".
So anyway i Googled exactly that, the responses i got were a bit ambivalent.

I thought you might be able to shed some light on this topic.

Again, sorry for the derail.

regards Simon

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Euthanizing South Australian Trees
since 2007

Treelore

A Burl is technically a cancer. It's a meristematic disorder and multiple out of control cell division.

Sean Freeman

There is a lot of confusion and disagrement as to just what causes burls, and just what is going on at a cellular level...so yes cancer is not a bad analogy, since what agreement that does exist tends to favour the view that what burls represent is disorganised uncontrolled meristematic tissues almost rupturing out from the tree....obviously uncontrolled is meant in a relative sense there has to be some control some initiator and some terminator but as yet the identity of either seems most unclear.

The articles that have been put up in response to the first post are very thought provoing and that is really what I was after...we/I may never get to the bottom of what is going on in this tree, but I'm hoping at the end of this little side journey i will have a much greater unerstanding of what could be going on, what might be going on in other trees. Its not earth shattering or anything like it but it just bugs me not to be able to provide a decent explaination of what I see in the tree.

To try to be a bit more precise in answering your question though playford....we do know that burls can be initiated by significant cellular disruption be that as a result of abiotic or biotic environmental factors.....certain kinds of herbicide can induce very disrupted new growth, burl like...fire and flood have been mentioned before, and I would not doubt that they could induce such responsive growth followingthe damage.
Parasitic plants such as mistletoe can produce localised disrupted growth. As can a number of fungi and bacteria...what is interesting int his case is the ongoing production of the growths in smaller diameter/younger branches, this tends to suggest an internal chronic problem, perhaps even within the DNA.

Treelore

agreed Sean but for all intents and purposes the cellular division that causes a burl is no different to the cellular division in a human tumor. The causes all may vary but the outcome is the same. One cell in a billion for whatever reason decides to divide in an abnormal fashion and the result is a growth that is not normal to the genetic structure. Getting to the bottom of why is like doctors trying to tell you how a brain tumor came about. Loose clarification but it's saturday and I'm not trying to be scientific.

playfordtree

Is that a yes/no or not sure?

Please "dumb it down" a little bit for me mate.
(pretend your talking to Homer Simpson)

I get a bit lost with all that technical jargon.
cheers

__________________
Euthanizing South Australian Trees
since 2007

blair duncanson

Firstly, must say that i do not hold as much scientific tree knowledge that several of you hold, so this is just an idea with no solid founds.
With ref to mistletoe.
Perhaps due to wet, smooth bark the deposited mistletoe seeds slid to the underside of the branches, germination of seed occured followed by the attack. Healthy tree responded to intrusion and continued to do so over the following years. Perhaps tree eventually won the battle and killed off the mistletoe in certain areas of the tree, (or mistletoe has a natural lifespan, that it had reached). Hence left with these bizzare growths on the underside of the trees limbs????
Grafts,
If tree was felled, would it be possible to wedge these grafts apart, what i mean is, is it true graft, cambium to cambium or is it healthy callusing due to external damage, ie rubbing branches??
Through experience of cutting through such,'grafts', i have found the callus wood to be much stronger than rest of timber found on the stem.
Be interested to see results if you ever get the chance to disect any of those growths. Seen them on a much smaller scale on a Nothafagus which naturally layered its lower branches, to enable spreading and i suppose some form of anchoring.
Interesting

Treelore

I give up apparently a lengthy version of scientific diatribe is what is needed to make something correct!!! a simple understanding of what may be is no longer acceptable

blair duncanson

Yep, think your right, the facts is what is needed. No harm in bouncin' ideas though, no matter what level.

Sean Freeman

Playford there's nothing wrong with yuo asking for this to be explained in a more understandable way.....Shigo often wrote if you can't explain/define something in less than 25 words you don't really understand it yourself! He would be suitably unimpressed by my attempts!

Burls can be usefully thought of as tree cancers yes, they are meristematic tissues gone nuts. My lack of understanding centers around what is initiating the process in this tree, and my suggesting that perhaps if it is in the genetics of this single tree this helps explain the very fluid like grafting (very much like ficus) that I see in this tree.

I will get to dissect one of the smaller growths (had conversations with GCCC and no objection to me taking one of the smallest higher ones) and will take photos to be posted here. Though it might be another two weeks as next week I'm in NSW.

crucificio

Hi, I dont know much about your eucs, however I have seen trees that have had their genetics rearranged by scientists so that they twist around or grow fat and then go thin again on their trunks, perhaps this is a natural genetic modification by your eucs (technically this would be like a cancer). also it could be that the man made air poisons have caused the tree to mutate, I have seen this happen near industrial factories. I may be completely wrong,would have to examine tree first hand to help any further, As for your grafting this is a common occurance with many trees when the branches "fuse" together. I have seen different species fused together and the larger tree become a host for the smaller, natural grafting? or something from afar?