daltontrees

I'd agree. Foliage of seedlings and very younbg trees is highly misleading sometimes.

Here's the core of what the case said about AG. "Examination has revealed that where it joined the main stem of the tree there was a depression or cup on the upper surface and at either side of that point of the branch there was the phenomenon of adaptive growth (“AG”) in the form of what Mr Forbes-Laird calls adaptive growth flares, and which some others call “bulges” or “ears”. These, it is agreed, would have been visible from the ground, and are very much at the heart of this action. In simplified terms AG is a biomechanical response by the tree to load stress on a branch, or to gravitational forces causing deflection of the branch, or as a “repair” response, for example, to some internal damage to the cambial cells on the outer surface of the wood of the branch. This autonomic response causes the normal annual growth ring process, programmed into every tree, to become exaggerated in thickness in order to reinforce or add strength to the branch at this point. In other words it is autonomic response by a tree to a stressed branch. "All agree that inspection of trees for safety purposes is carried out from ground level – a system called visual tree assessment or VTA, first defined by Professor Mattheck. It is based on inspection from ground level and does not require any aerial examination. The depressed area I have described above would not have been visible from the ground. The claimant’s expert estimates that the AG flares had been in place for 5-10 years. At some later stage a crack or fissure had developed in the central upper surface of the join as a primary failure due to stress and this had led to oxidation and water ingress into the wood of the branch at this point. This too would have been impossible to see from the ground. Once this crack process started it is said that a secondary failure leading to the shearing from the branch of the stem was inevitable. "At the heart of the claimants’ case is the proposition that the mere presence of the AG at this point was a warning sign of a possible failure and meant that further investigation of the join was indicated. The defendant’s case is that AG is a frequently found feature on many if not most mature beeches of the age of this tree." The case is worth a read as it has all the drama and suspense of a Detective Dendro story...

Point taken. The words 'to generate' impliesd thought too, so maybe the words 'modified to create' shoudd be replaced by 'different, resulting in". Shigo's not half as bad as Mattheck and Breloer for dippy anthropomorphisms. I like to stick to the observable and let others have their version of the metaphysical.

I have just been through Bowen v National Trust, Micklewright v Surrey, Atcins v Scott for relevant references to the terminology. Only the first has any, but boy does it use adaptive growth in spades. So much so that in the written judgement it has to be abbreviated to AG it is used so many times. But in a nutshell it is described by the juidge as a 'phenomenon', not as a kind of wood. I'll rejig my notes for the useful bits there and that btggaz quoted from Shigo. And hopefully it wil all materialise as a plain english unambiguous authoritative set of definitions in Wikipedia. It's a start anyway. I have a daunted sense that we are really only in the paddling pool messing about with the definitions.

There's 2 Trees of heaven near me, so I popped by a couple of hours ago to check. The twigs, just coming into leaf, looked pretty much identical to your photos, including withered tip. I'd say 99% sure yours is A.a. But would love to see confirmation in due course.

Thanks for taking the trouble to type this all out. It's what I needed to know. In short Shigo supports if not originally puts forward the definition of reaction wood as being based on resistance to gravitational stress, specifically leaning stems and branches. I'll tidy this all up in a day or two.

The Daily Mail quoting Nigel Farage quoting the @pink Book'. You are being led to believe...

And Norway Maple is Acer platanoides the 'plane-like maple'. The leaves are pretty similar to P x h.

That'd be mt question too. I'm fairly sure it is one. There is no pore surface and it is exhibiting the bark spitting you would expect on oak.

As someone else has suggested it may be an indicator of Armillaria mellea beneath the bark. If it has h killed cambium, the area would be susceptible to the usual bacterial infections normally assocuated with bacterial cankers. That's what it looks like anyway.

Nice as ever to have someone else contribute to this. I will make a few changes to the Wikipedia definition for your last cvomment but just remember I am not trying to invent anything here, just trying to make sure that the Wiki definition reflects established sources.

Looks like an aluminium tree tag to me...

Looks like fire damage alright. Especiually if in a public ark or up the back of a garden where garden rubbish might be burnt. Reasonable callus forming, in time it might heal over, but not terribly likely on an older tree. A straight race, fungi versus callus.

Some definite improvements. Will look it over later.

A large Ash came down in the last big storm and it obviously had been rotten/diseased for some time at the base and formed reaction wood to support the tree on what was left. This area was less than half the original area of the trunk. When I cut it with a sharp chainsaw, I thought that I must have caught the blade as it was hard as hell and the saw went off at an angle. I stopped sawing and tried the saw on another branch which it cut easily. So I left this substantial block of wood on one side as it seemed so unusual. Is this reaction wood sought after for carving. turning or other purposes? I don't know. It soulds like classic tension wood, very very rich in cellulose and hardly any lignin. It would I imagine be very dense. The rings can be very close together, and sometimes tension wood can be almost white. Maybe the turning guys will come along in this thread and comment? If you had bother cutting it, so might they.

Attached is what I was thinking of for the amended definition in wikipedia. Wikipedia edit.pdf

Because they have evolved that way. To succeed in their niche. Disposable fast colonisers vs repairable long-stay.

Jomoco, I am pleased to have anyone pitching in. Sometimes I noticve that hundreds of people have read this thread since a couple of days ago yet only a few (mainly from USA?) bother to comment. We are not disagreeing. I agree entirely that all wood has the pre-disposition to react to all sorts of circumstances. I also agree stresses can be mechanical (flexure) or gravitational (weight) or intermittent loading (snow or foliage). Or bits of all 3 at once. Hence my comment to treeseer that 'all wood is interaction wood'. I'm just saying that the words 'reacton wood' have alredy been defined by others to be restricted to situations of gravitational forces. We may need another term for flexure wood, but trying to lump it in with reaction wood won't help. To pout it another way, if reaction wood is as Lonsdale purports explicable by gravitational relocation of growth-inducing auxin, then butress wood cannot be reaction wood. There may be another mechanism, at cellular level, that is triggering the production of wood of particular quantity and/or quality where there are regular flexure stresses at the base of an upright tree.

Not so. Wikipedia says "Reaction wood forms when part of a woody plant is subjected to mechanical stress, and helps to bring parts of the plant into an optimal position. This stress may be the result of gravity, wind exposure, snow buildup, soil movement, etc. " This is closer to the definition of adaptive growth. The point Im trying to get across is that all the reliable definitions (including ISA, thanks for that) say it's a response to gravity on leaning stems or limbs. At least that's what the tea leaves are telling me. Maybe I've had too much tea. And yes, it's all being researched in the interests of , well maybe not fun but the satisfaction of furthering better understanding. Wikipedia's great a lot of the time, I use it daily for various things, but the quality is a bit variable. The reaction wood definition is definitely wrongly cited and syntactically wrong and also is wrong. 3 wrongs don't make a right.

Oh, got you now... a workout for the branch attachments. I like it! The bowling balls would be fab too. So how are the baskets suspended? Have you put a sling around the branches, or bolted them?

That's a really good article but I don't agree with you and here's why. I am not trying to prove or disprove why or how reaction wood forms, I am just trying to dispel some of the bogus definitions. The interrelationship between thigomorphic wood reation wood, negative-geotropically influenced wood, well-nutritioned wood etc. is definitely blurred, overlapping and subject ot any number of poorly understood feedback loops, but ultimately reacton wood is defined as forming to combat gravitational loads. Indeed, your cited article says as much by defining reaction wood as "wood with distinct anatomical characteristics which, in dicotyledonous trees, occurs on the upper sides of branches or leaning trunks in areas subject to tensile stresses (tension wood) and can perform a straightening function." Because butresses and upright butts just aren't branches or leaning stems, they can't have 'reaction wood'. But clearly they can and do exhibit adaptive growth, which your article explains is characterised by increased wood density as well as butress height. However, the increased density could be due to increased lignin to support self-weight of the trees as they get bigger. Elaeocarpus is an angiosperm, and reaction wood in the strictly defined sense should manifest itself as topside cellulose-rich tension wood on branches. I am not seeing how this is comparable to topside (possibly) lignin-rich compression wood on butresses. The whole thing would be simpler if we scrapped the reaction wood distinction and talked of compression-adapted wood and tension-adapted wood. This would take gravity out of the equation and might lead to a better understanding of the mechanisms behind the adaptations. I'll put the kettle on and have another think about it.

Most interesting, but am I issinbg something? How are you planning to measure and analyse the results? Will you be cutting off the branches after a few years and measuring the growth increments?

I think I may correct the entry in Wikipedia for 'reaction wood' as it is plainly wrong (see attachment in earlier posting). Anybody got any thoughts on this before I do it?

I'd go with Gyromitra, it pops out in spring, and has a strong association with Pinus. A killer, by all accounts. And a nice find. Can you say where it was?

Uh-oh! A raw nerve touched there?. Good eloquent rant, though. Based only on the paper that you sent the link for, Telewski has shown only that young Poplar stems small enough to be bent by hand through 40 degrees or so will develop elliptical cross sections with a reduced modulus of elasticity. He hasn't proven that this would happen in other species, or wold happen and continue to happen in mature specimens or those that would at maturity (unlike Poplar) develop heartwood. So on a strictly scientific basis I would say that the paper hasn't proven any universal principles. It's certainly a good start though. Wouldn't it be wonderful to rig up a more mature excurrent tree (ina sheltered location) near its top and pull it repeatedly from the ground like in the Telewski experiment and then see if it too develops a modified cross section. I would be interested to see too how any changes in mechanical properties of the wood (cellulose/lignin/cell length/cell density etc.) had been achieved by the adaptive growth. A few cores cut to thin section could do this. Anybody got a few £000 they want to donate to the furtherment of dendrology?