Listening for decay

[sloth]

Good fun That first reading is a little odd, was it taken at the level of the fb, or higher/lower? And are you going to be gettin a cross section!?

[David Humphries]

Good fun That first reading is a little odd, was it taken at the level of the fb, or higher/lower? And are you going to be gettin a cross section!?

 

Interesting for sure.

 

The resistograph readings were all taken at 150mm height from the ground, which is just above the fruit body.

 

The tree has been subject to reduction, so I don't believe it's crying out to be removed at this time.

 

I'll assess it again in 12 months.

 

When we're next over there, we'll carry out a QTRA on the tree just out of interest.

 

 

 

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[sloth]

Sounds good, are you qtra registered then?

[David Humphries]

Sounds good, are you qtra registered then?

 

No, I've chosen not to take that particular route.

 

One of our team is.

 

 

 

 

 

 

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[treeseer]

That first reading is odd indeed.

 

Any thought to getting the dirt off the stem and finding the flare?

[David Humphries]

Any thought to getting the dirt off the stem and finding the flare?

 

I hadn't considered that a particular issue here Guy.

 

 

 

 

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[treeseer]

I hadn't considered that a particular issue here Guy.

 

 

 

 

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Why not? No Rx without an RCX is the rule here. How can care be prescribed without examining the root collar? Are there roots down there at all? Seems daft to go to all that work to assess trunk whilst ignoring roots, which after all hold the tree up.

 

Wood decay is at ground level, maybe where mower or strimmer gouged it. Curious enough to drill four holes, merrily breaking codit barriers, but no dirt removed to expose the the site and eyeball and probe it?

 

no offense meant but that defect-centered approach is what i hear brits deride about american arb, yet here you're doing the same. Don't mind me; haven';t had my tea yet. Ta.

[David Humphries]

Why not? No Rx without an RCX is the rule here. How can care be prescribed without examining the root collar? Are there roots down there at all? Seems daft to go to all that work to assess trunk whilst ignoring roots, which after all hold the tree up.

 

Wood decay is at ground level, maybe where mower or strimmer gouged it. Curious enough to drill four holes, merrily breaking codit barriers, but no dirt removed to expose the the site and eyeball and probe it?

 

no offense meant but that defect-centered approach is what i hear brits deride about american arb, yet here you're doing the same. Don't mind me; haven';t had my tea yet. Ta.

 

Great points Guy, no offence taken.

 

Did you get ya cup 'o' tea, and if so did it calm ones anxieties?

 

 

ofcourse both tree health care & tree risk assessment can be carried out together, and to some extent one informs the other.

 

In this case (rightly or wrongly) I have not had the health of the tree as a primary concern.

 

There appears to be a relatively healthy canopy with plenty of buds and very little (almost no) die back. As such, my focus has not been on the roots.

 

This thread (& the addition of this tree to the thread) is about listening for evident decay not particularly vascular health.

 

The basal trunk (though not root) decay of the Rigidoporus (plus also the cavity up the stem) was/is my main focus here.

 

I'm sure you've probably noted on other threads that tree (root) health is actually on my radar too, no?

 

 

 

 

 

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[treeseer]

ok, i figgered the rigidiporus was a stem issue and reason for that focus, but...

 

still having trouble comprehending roots as a health/vascular and not a structural/risk issue

on any tree

roots after all hold them all up, no?

 

having the flare hidden seems an extreme limitation on any risk assessment

[daltontrees]

I have been following the experiment with great interest. I know nothing much of resistographs except the general principles. I have, by the way, got myself a nylon hammer (hey, and a stethoscope for interest). So my comments are more by way of my education than of any serious input.

According to Weber and Mattheck in Manual of Wood Decays, one of the disadvantages of the resistograph is that 'only advanced white rots give reductions in drilling resistance'. If the fungus is indeed Rigidoporous ulmarius, according to the AA guide 'Fungi on Trees' it is a brown heartwood rotter (and so is leaving the cellulose intact at least initially or until another secondary decay makes its presence felt). Is this a possible part explanation for the odd readings particularly the first one?

I just noticed as well that Weber etc. sugggests another disadvantage, that tension wood shows increased resistance to drilling, as does early stage white rot. The odd first reading was on the east side, not normally the tension side, but the fungal growth looks to be appearing at a vertical weakness as might be expected and might there therefore be a predominance of tension wood there?

Apologies for wild speculation and book learning as a distant substitute for informed debate. I would be interested in any comments though.

Edited April 25, 2013 by daltontrees