Water use for tree defences??

[stevelucocq]

Hi,

 

I am in the process of getting ready for my Tech Cert written exam. There are few questions on the processes and importance of water in trees…ok nothing too unusually there but there is mention of how water in wood is important for the trees defences againist decay…. ok I may be off the point with this but I am aware of Shigo CODIT but if water is lacking in the wood does this allow decay to take hold as oxygen is present and if the wood is dry is therefore non-functional and cannot respond? or perhaps I should just concentrate more on the Business, Management and Legislation Stuff than worry about little things??

 

Thanks Steve

[David Humphries]

Steve,

 

many fungi exude water from out of the Tree, and pass it through it's Fb, to provide a more conducive environment for it's own decay strategy.

 

Inonotus dryadeus is the classic, I've also seen it on Ganoderma.

 

AIE. Arboricultural Information Exchange. look up I.dryadeus

 

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Edited May 11, 2009 by Monkey-D

[stevelucocq]

arh is that why some on here said that removing the Inonotus dryadeus fruting body can slow down the speed of the decay of this fungi as the method of removing the water through the fruiting body is removed and the wood remains less favourable ie wetter?

[gibbon]

A higher water content means a more anearobic environment which is less that ideal for most fungi which require oxygen.

[stevelucocq]

yeah here is a few pic from last year but never thought of the connection between the FB altering the condition of the wood to suit the fungi (cheers)....I have taken some new pictures this week of I think some small FB of Inonotus dryadeus on my camera which I may down load later...cheers steve

[Paul Barton]

Here is another fruiting body showing the water droplets. Inonotus hispidus I think.

[stevelucocq]

thats a beauty!!...looks like it...anymore pics and it looks like its on ash?

[David Humphries]

Have posted this before.

 

I. hispidus on Ash from last year.

Although not exuding droplets, you can still note how saturated the brackets are.

 

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[Giles Hill]

I got the impression that the concept of brackets inreasing water loss - as a method of making a more favourable environment - was quite a recent idea, rather than an established 'fact'?

 

I was also thinking that brackets of some species are ephemeral features, but the fungus still manages to rot the tree when the brackets aren't there.

 

The idea that brackets help dry wood to improve conditions for fungal decay sounds feasible, but I'm not sure it's something the examiners would expect you to come up with.

 

I've had (am having) difficulty with the wording in some of the previous Tech cert exam questions, but if I had to answer the above question now, I'd be thinking along the lines of how water is an essential part of photosynthesis and therefore the tree needs water to generate new material to compartmentalise decay, form adaptive growth and generally be in a healthy enough condition to deal with the decay / respond to it quickly.

 

I'd include a note about brackets being a possible enhancer of dehydration, but I'd make it clear that it was an idea I'd heard at a David Lonsdale talk and to the best of my knowledge, it's expert speculation rather than accepted fact.

 

I don't know if I'd pass on this basis...

Edited May 12, 2009 by Giles Hill

[David Humphries]

I

 

I'd include a note about brackets being a possible enhancer of dehydration, but I'd make it clear that it was an idea I'd heard at a David Lonsdale talk and to the best of my knowledge, it's expert speculation rather than accepted fact.

 

I don't know if I'd pass on this basis...

 

 

With due respect I disagree Giles, as this "idea" is most definately not just of recent provinence.

I remember talking around this even back when I took the tech cert in '99

 

I would'nt get hung up on what's in vogue in the current circulation, many if not all our hypothesis have been pondered on by Tree people at one time or another.

 

 

 

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