sean freeman

Hama, its fine to assume that the compressive and tensile properties of a core sample reveal something more than the properties of that core sample. Tables of material properties of living wood are very difficult to produce empirically without creating enormous caveats and limitations on how the values can be extrapolated hence the importance of Stuttgart table of wood strength (Wessolly and Erb 1998).

Yes.....I know of an extracted core sample, cut and pulled out of the stem rupturing vascular connection disrupting cell turgour and arguably creating cell laminar shear failures in the process. ...and the material properties that these values are being compared to are derived how? Hama, other researchers are very very careful to explain the limitations of applying statistical value sets to individual trees...ie Wessolly et al...the maths matters, just how far you can push the modelling before the values become meanigless matters.

Magic numbers is a description Claus used when talking about the mathematical relationship between the numbers derived from the fractometer and the material properties of the standing, living tree the last time I was lucky enough to hear him speak back in 2004. Again I think it is a potential trap that over simplification leads you into every time.

To me the issues are fairly simple when it comes to what problems have been identified with the research presented to support the t/R ratio 'rule'. I have also spoken to Claus and found him quite personable and friendly, I don't place him nor anyone else on a pedestal...not because I want nor need to feel their equal, I try and evaluate what it is they are saying based on my understanding....if there are significant problems in my mind with some of their arguements I try and engage with them to clear up what might be at the heart of that. Claus Mattheck, like David Lonsdale, Alex Shigo and a few others have undoubtable altered the way we perceive and conceive of trees. I would also suggest that Colin Tudge has done the same, anyone who has read "The Secret life of Trees" will never think about trees in quite the same way. The problems for t/R are laid out in those papers I attached previously...you don't need to have an intimate knowledge of Statics to understand why providing all the data collected is quite important when making a claim of statistical significance between only two variables. Claus himself in 2006 showed that the relationship for t/R was statiscally random...in other words no single t/R value exists that predicts stem failure. This is presented quite clearly in Jerry Bonds paper. Unfortunately there are a great many consulting Arbs providing advice (for a fee) applying the t/R ratio as if it were a golden rule....this is not Claus's fault, but it is simptomatic (IMO) of what happens when you try to reduce complex relationships down very simple formulae. From my perspective much of the criticism of the supporting evidence for tR or some of the other areas of Claus Mattheck's research of don't lead me to devalue VTA or its underlying principles....it does make me suitably dubious about anyone that lays claims to have magic numbers in relation to tree strength or tree "safety".

Very well put Andrew. Personally I have absolutely no problem with the way Claus presents VTA, in fact I have spent not insubstantial amounts of money to benefit from those very presentations. I am very uneasy with the way in which "golden rules" have emerged out of some of his work, and some of the problems identified in the data by those who assisted with his research, and by others reviewing his research. Simply because there is disagreement on aspects of interpretation and presentation does not mean that fundemental flaws exist, it does mean that those who want to apply broad sweeping statements in the application of pure mathematical formulae really should be aware of the criticism that exists, as well as the adulation. barcelona_2005.pdf Risk%20Bond%20%20over%20r%20debunk[1].pdf how_hollow_a_tree.pdf

I would suspect the latter but luckily the microorganisms don't mind either way.

David, does this particular LA have a policy regarding retention of standing deadwood as part of their Biodiversity action plan...or something similar?

I suspect that for most of us who are not mycologists coming to terms with the refusal of many/most fungi to stay in their categorised boxes - Saprophyte/Parasite is a long and laborious process.

Here you go Paul top of the list on the page Downloads

I certainly agree with this I believe Mike Ellison's public letter in response to the NTSG consultation is most succinct. I certainly like to think that the pics are showing us a LA endeavouring to begin that process of engagement, it is to be sincerely hoped that they have a workable, working strategy behind the public notice.

Lot of arguement over these fruiting bodies I can tell you. Hopefully these pics are slightly better definition:

No? You are right its more likely to be G.lucidum or G P. Karsten sp. here but for all macro characteristics almost indistinguishable from your G.resinaceum.

Some shots of juvenile G. resinaceum (IMO) making hay on the roots and root crown of Delonix regia (Plam Beach, Gold Coast). There was some disagreement with the State Authorities (DPI) about the ID, some talk about Phellinus noxius. We were asked to provide advice and suggest a contractor to undertake soil works...I have not been back to the property but understand after initial apparent improvements the tree continues to struggle with its unwelcome guest.

I don’t disagree with the points made about Local Government resources and that perhaps the works are not quite what others would be able to achieve. I really hope the LA has managed to engage with some community/school groups to highlight not only why they have carried out these works but to raise the profile and the value of standing deadwood and declining trees retained in the urban environment. As for the points about risk…….Provided the trees were assessed by a competent qualified person with an auditable methodology….and target exposure to large part or total tree failure was determined not to be unacceptable…then I see no major intrinsic problem in retaining the trees like photographed.

Just brilliant pics, they really do look like they re engaged in some extreme slow mo dance or an almost never ending arm wrestle (which is how my own attempts at dancing have been described by some unkind persons!) But beautiful pics David.

From a visit to veteran figs in the Tallerbudgerra Valley came across this lovely bright red Aseroe rubra Anemone Stinkhorn or starfish stinkhorn, growing in the grass next to a young Macadamia sapling.

Yes David, usually I do but I don't own a knife and rely on my friend and colleague for her budding knife...she did not have it with her on this walk hence no shots...also I would have been loathed to cut it despite it being very very common having never seen one so well formed..I know daft...but there you are. I also thought it was a grub and have shots of another fruiting body that was being eaten...attached below...but this was in fact the tip from the ubiquitous sheoaks all around the area (Allocasuarina glauca)...like I said I made the same error pointed out by my far more observant companion

Hi Andrew, I suspect that Nev is expressing what he hopes is the future course rather than a deterministic prediction for the future of Arboriculture. I often feel that more progress (from my perspective) can be achieved through dialogue with other professions than with other Arborists. There are in Ted Green's words a lot of "flat earth Arborists" refusing to move on from their (hard earned) business model of chainsaws, chippers and 'dangerous' trees.

From the same walk yesterday...a case of identification confusion...could be either Phellinus badius or Phellinus robustus, the two are so very similar and really only possible to seperate through microscopic analysis of the spores, my text for wood decay fungi in Queensland (Hood) suggests that spores from Badius are slightly yellow/brown where as Robustus are colourless.

A few shots of a colourful fella from yesterdays wanderings through Coombabah wetlands here on the Gold Coast Qld. Pycnoporus sanguineus is a fairly common saprophyte and one I have seen many many times but this was the largest fruiting body I have come across and had almost formed a disc...It commonly forms a small shelf without anything that might be described as a stalk.

Hama, we are all wrong most of the time when it comes to trying to interpret the complexities displayed in the trees we visit, Claus included....though I agree his seminars are thought provoking and very stimulating. I firmly believe professional ego is one of the greatest obstacles to progress, that having been said, you have a group of Arbs here on this forum that share pictures and thoughts that (for me at least) reflect where I hope our profession should be heading:001_cool:. It is a great relief to find that the small group of tree passionate people I mix with have a group of fellow travellors amongst the ranks of UK professionals:001_smile:.

I think you have explained yourself well Hama, and the picture (which I have seen before in a slightly different form) is very good too:001_cool:...however in terms of explaining the small number of trees that exhibit this braided or chequered pattern I am not convinced that the description is completely accurate nor that the concepts of greater levels of cellulose over lignin satisfactorily describe what we are observing. Hopefully in the next 12 months some funding will be gained to (amongst other things) enable microtomes to be cut of this 'braiding' and a clearer idea of how the cells might differ in crosssection can be gained. Rate of growth may well be a big part in this, however many individual trees with this characteristic have established in open ground with insiginificant competition, trees (of the same species) in virtually identical growing conditions do not manifest the characteristic. Other (apparently) equally fast growing Eucs do not seem to manifest the patterning. It is reported in Hornbeam (A.Cowan) amongst other UK species...not sure that this species fits the criteria described? I think there are a range of factors at play, cell structure is a big part of it no doubt. It is worth reminding ourselves that wood cells are by their physical construction (irrespective of lignin:cellulose ratios) much stronger in tension than compression, and that the pre-stressing of cells plays a critical role in maintaining structural integrity within the tree or its parts. Cassian Humphreys is putting together an article for the Arbor Age mag here in Oz detailing his observations of what he has coined 'Braided Reaction Wood', I will direct him to this thread your thoughts will doubtless be of great interest to him as well.

Often placed under the less than helpful term thigmomorphogenesis.... Here are a few pics that are representative of an unresolved discussion between some very well known Arbs over there, over here and in the US. Unusual but certainly not unknown in a number of different tree species, interested in any thoughts others might have.

I don't David, but I hope to get some kind of response from an email I am sending the visitors centre regarding the trees and their significance...I'm sure they are aware of the attraction they represent hence their retention in such close proximity to the main drive. Just what the history of this group of trees is I really don't know....there is nothing as impressive for miles around (at least as far as I could tell from the road....I know hardly definative!) I am unaware of any solid work on the ecology associated with River Red gums, there are a couple of theses to be published soon coming out of Tasmania regarding long term studies into deadwood fungal associations on 'old growth' (100 -150yr old) logs. When these are only published within a uni or other education institution they can be difficult to access. The same Tasmanian research site has produced some excellent work on obligate beetle relationships to the older deadwood. The Uniqueness of Habitats in Old Eucalypts:

Some shots from Jacobs Creek South Australia May 2010. All Eucalyptus camaldulensis (River Red Gums)