Armillaria investigation

[David Humphries]

David, to what extent do you consider whether the early removal (stump and all) of Armillaria victims as food sources for further spreading to adjacent stock? This is not a loaded question and I don't think there is a right answer, I am just curious about your perspective on what is for me an age-old dilemma.

 

Depends largely on location, site & objective.

But I tend towards the health of the remaining trees to be the key.

Poor rooting environment will probably lead to stressed trees which leads to attack.

 

Perhaps leave the stumps for the Armillaria to devour as a diversionary tactic.

 

 

 

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[daltontrees]

Depends largely on location, site & objective.

But I tend towards the health of the remaining trees to be the key.

Poor rooting environment will probably lead to stressed trees which leads to attack.

 

Perhaps leave the stumps for the Armillaria to devour as a diversionary tactic.

 

 

 

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Noted. I still carry in my head the extreme zero tolerance treatments suggested by Strouts in "Diagnosis of ill health in tree". I am watching in my local park the trees near a recent A.m victim, the nearest one has extensive dieback and won't recover. The next one has generally declining vigour and the third has isolated dieback or poor vigour. Beyond that the trees are OK. Soil conditions poor (grass, compaction, waterlogging, leaves cleared). An inevitable slow-motion domino effect.

[treeseer]

Have you had experience of return visits to trees that have been subject to Armillaria then had soil amelioration undertaken?

 

 

 

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Talks there were only ~20 minutes. Luigi was talking a mile a minute, in Italian of course, but he was kind enough to send me the pdf.

 

Yes I've gone back to see Arm infections dried out and closed up; I'll get a pic of one today. I credit simple exposure more than soil amelioration with most results. Inadvisable imo to cover exposed areas with soil.

 

Jules, are those assumptions based on science, or faith? I don't follow the logic.

[daltontrees]

Talks there were only ~20 minutes. Luigi was talking a mile a minute, in Italian of course, but he was kind enough to send me the pdf.

 

Yes I've gone back to see Arm infections dried out and closed up; I'll get a pic of one today. I credit simple exposure more than soil amelioration with most results. Inadvisable imo to cover exposed areas with soil.

 

Jules, are those assumptions based on science, or faith? I don't follow the logic.

 

I haven't made any assumption, I have just observed. The trees are dying one by one in sequence and when one gets felled by the Council I check and sure enough there are A.m rhizomorphs. The trees are dying standing, cambium seemingly killed ina 2 year period. Coincidence?

[treeseer]

Sorry to be anachronistic; I was asking about assumptions like

"...the net removal of a large amount of ripe buds will set the tree back considerably."

It might set back growth perhaps, but advance the tree's health condition.

 

and "In spring when it flushes it may not have enough transpiration suction for proper vascular function..."

If there is less distance to suck, is that not a benefit that mitigates the loss?

 

"...and needs to expend its reserves on redressing the root/shoot balance,

or roots will die."

What if the tree had resources stored sufficient to cover the loss?

 

"It may bounce back but at quite a cost."

Or at no cost?

 

"Meantime the fungus marches on.

What if CODIT happens?

 

"There is room for an argument that the removal of canopy removes the energy sourve of a pathogen and slows its development. But if the pathogen is feeding on cellulose and/or lignin, it won't be slowed at all. Net gain for pathogen. Could tip the balance. Worth a go in a 'nothing to lose' scenario."

Sorry not following that last bit at all.

[RDB logs]

Very interesting David thank you for sharing, can you let us know the long term outcome of the tree. I guess you won't get chance to look again in a years time?

[David Humphries]

I've passed this tree every work day for the last thirty years so there may be a decent chance that I'll update the thread next year

 

 

If the oportunity arises, I may take chlorophyl fluorescence readings across the canopy to try to ascertain the vitality of the tree.

 

 

 

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[Paul Barton]

 

If the oportunity arises, I may take chlorophyl fluorescence readings across the canopy to try to ascertain the vitality of the tree.

 

 

 

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Have you bought an arborcheck thingy?

[David Humphries]

Have you bought an arborcheck thingy?

 

No Paul, we've not gone down that route yet

 

 

 

 

 

 

 

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[daltontrees]

Sorry to be anachronistic; I was asking about assumptions like

"...the net removal of a large amount of ripe buds will set the tree back considerably."

It might set back growth perhaps, but advance the tree's health condition.

 

and "In spring when it flushes it may not have enough transpiration suction for proper vascular function..."

If there is less distance to suck, is that not a benefit that mitigates the loss?

 

"...and needs to expend its reserves on redressing the root/shoot balance,

or roots will die."

What if the tree had resources stored sufficient to cover the loss?

 

"It may bounce back but at quite a cost."

Or at no cost?

 

"Meantime the fungus marches on.

What if CODIT happens?

 

"There is room for an argument that the removal of canopy removes the energy sourve of a pathogen and slows its development. But if the pathogen is feeding on cellulose and/or lignin, it won't be slowed at all. Net gain for pathogen. Could tip the balance. Worth a go in a 'nothing to lose' scenario."

Sorry not following that last bit at all.

 

I surrender, I don't know what I am talking about.