Reaction wood

[jomoco]

If Telewski can't help yu after spending his life studying and publishing on the subject?

 

http://treephys.oxfordjournals.org/content/20/8/535.full.pdf

 

Best regards mate.

 

Jomoco

[daltontrees]

If Telewski can't help yu after spending his life studying and publishing on the subject?

 

http://treephys.oxfordjournals.org/content/20/8/535.full.pdf

 

Best regards mate.

 

Jomoco

 

Thanks for that, I love it when people take the time to conduct properly controlled experiments and present the findings in good clean english.

 

The article provides these useful snippets.

 

"Jaffe (1973, 1980) used the term “thigmomorphogenesis” to describe the physiological, biochemical and morphological responses of plants to wind and other mechanical perturbations. Thigmomorphogenesis can prevent stem failure caused by wind loading, by reducing drag or increasing mechanical strength.

 

"Plant responses to wind have been characterized extensively in gymnosperms, and to a lesser extent in woody angiosperms. In gymnosperms, morphological responses to [mechanical peturbations] include formation of an elliptically shaped stem cross section, with the long axis in the direction of flexure, and decreased stem height..."

 

For those who don't want to read the article, the summary is that the stems of Poplar that had been bent repeatedly became more flexible and developed an elliptical cross-section.

 

It's a pity that no observations were made about how the trees adapted the quality of wood (i.e. whether by increasing cell density or changing proportions of lignin or cellulose. Also the stems weren't left to mature and turn their new growth into wood.

[Gary Prentice]

I think I have a copy of the dictionary at work, if you still need it, if I get chance I 'll pick it up later today.

[treeseer]

Thanks for that, I love it when people take the time to conduct properly controlled experiments and present the findings in good clean english.

A lovely compliment, even more so coming from England! The author will be pleased to hear it. My favorite snippet comes from his early professor: "All wood is reaction wood."

[daltontrees]

Emm, Scotland, actually. We speak english up here too.

 

What a great exam question it would be to have "All wood is reaction wood. Discuss."

 

But if you accept the analysis in my research here, based as the conclusion is on Lonsdale's work (now there's a man whose command of the english language delights), the answer to the question has to be 'No, it isn't.' But if you wanted to say "All wood is interaction wood", I'd have to agree.

[daltontrees]

I think I have a copy of the dictionary at work, if you still need it, if I get chance I 'll pick it up later today.

 

Please do.

[treeseer]

Emm, Scotland, actually. We speak english up here too.

 

What a great exam question it would be to have "All wood is reaction wood. Discuss."

 

But if you accept the analysis in my research here, based as the conclusion is on Lonsdale's work (now there's a man whose command of the english language delights), the answer to the question has to be 'No, it isn't.' But if you wanted to say "All wood is interaction wood", I'd have to agree.

My apologies; no offense intended. Yes, it'd be a great discussion, but once terms are carefully defined, it might not be a long one.

 

over a pint, perhaps.

[daltontrees]

Surely you mean a half litre? Only joking.

 

I get really cheesed off with people destroying the language by making up words, and with other people using words they don't know the meaning of because it makes then sound smarter than they are. All words in professional usage ought to be defined, I think.

 

Just heard a football commentator on the radio talking about a team delivering the 'coo de gra' presumably mixing up the pronunciations of coup de grace (pronounced coo de grass) and foie gras (pronounced foy gra). In the end he just sounded like an imbecile. Not life-threatening or even that important but if he had just said 'killer blow' he would have got away with it.

[jomoco]

What cheeses me off?

 

Blokes professing they understand reaction wood formation, or thigmomorphogenesis in trees, yet remain mum when their industry leaders in the ISA embrace such "snake oil" new products in our industry like Cobra Dynamic Cabling Systems, so popular now in Europe and the USA!

 

When you actually understand what Telewski's proved beyond the shadow of a doubt?

 

Perhaps then you'll have something worth really gettin cheesed about mate!

 

Pruning before cabling, as Telewski shows trees do naturally exposed to hard prevailing winds. And cabling only in the case of an identified structural defect, with the intention of maintaining that artificial support for as long as possible.

 

That the ISA even considered Cobra's BS sets my teeth to grinding!

 

Just my opinion of course...

 

Jomoco

[daltontrees]

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?