Body language Quercus

[Fungus]

1. I have observed similar exudates on Fagus, Betula and Acers colonised by Armilaria but I have never tasted them before.

2. Why are the exudates associated with cambium necrosis caused by Armillaria different from those associated with Phytothera ?

3. What is the fate of the Quercus robur with Phytophthera ramorum infection. Is there a policy of removing P. ramorum infected trees for control of the disease in the Netherlands.

4. Have you seen P.ramorum with the ability to colonise and kill healthy trees or have the infected trees been stressed or in decline already.

 

1. Only the exudates of Quercus robur smell and taste sour, because of the "vinegar" acids. The fluids from Q. robur and beech have no distinct smell or taste and the exudates of Acer, Platanus and Betula smell and taste rather sweet. Besides, apart from taste and smell, there is the ELISA test for identifying Phytophthora.

2. Because the Phytophthora oomycete changes the composition of the cambium fluid and the mycelium and/or rhizomorphs of Armillaria don't because they just block the transport in cambium and sapwood.

3. Most of them survive, but are in poor condition (partial defoliation) and become vulnerable for attacks of other parasites. Because infection with P. ramorum is associated with the massive deposition of ammonia on bark and leaves of trees from the everywhere present maize fields, there is no policy on removing infected trees. And do bear in mind, that contrary to what some sources state, a P. ramorum infection is not the same as Sudden Oak Death, a disease which still is not documented from The Netherlands.

4. Yes, although small wounds facilitate infection of the tree with spores.

Also see my album Rhizomorphs Armillaria.

[Will Hinchliffe]

Thanks for the reply. All very interesting. I think advice thats coming out on P.ramorum in the Uk needs to be reviewed. The interpretation of the science has been confusing.

[Fungus]

Extreme buckling on Q. rubra after an infection with Laetiporus sulphureus brown rotting the central wood.

 

Another example of extreme buckling of the trunk base of a Quercus rubra infected by Laetiporus sulphureus.

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[sloth]

Another example of extreme buckling of the trunk base of a Quercus rubra infected by Laetiporus sulphureus.

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May I ask how you can tell it isn't fistulina brown rot without seeing mycelial mats in the wood, or fruit bodies?

[Fungus]

May I ask how you can tell it isn't fistulina brown rot without seeing mycelial mats in the wood, or fruit bodies?

 

Fistulina hepatica only lives in/on Quercus robur (and Castanea sativa), because its mycelium needs the vinegar acids from the annual sap wood rings to grow inside outward before it starts producing mycotoxins, with which the cambium is killed, so it cannot be found on Q. rubra, as it lacks the necessary high concentration of vinegar acids (also see : Album Fistulina hepatica).

Besides, the mycelium of F. hepatica causes a bark necrosis, which is distinctly different from the buckling caused by L. sulphureus.

[Bundle 2]

3. Most of them survive, but are in poor condition (partial defoliation) and become vulnerable for attacks of other parasites. Because infection with P. ramorum is associated with the massive deposition of ammonia on bark and leaves of trees from the everywhere present maize fields, there is no policy on removing infected trees. And do bear in mind, that contrary to what some sources state, a P. ramorum infection is not the same as Sudden Oak Death, a disease which still is not documented from The Netherlands.

 

Very interesting. Some excellent information Gerrit!

Are you saying however that the current interpretation and advice being given by the FC is in fact a bum steer?

( to be fair....Im not sure FC uses "Sudden Oak Death" but google quickly leads you to FC and advice on P ramorum...the association is clearly evident...! )

 

Sudden oak death - Wikipedia, the free encyclopedia

 

Tim

[Fungus]

Are you saying however that the current interpretation and advice being given by the FC is in fact a bum steer? (to be fair....Im not sure FC uses "Sudden Oak Death" but google quickly leads you to FC and advice on P ramorum...the association is clearly evident...!)

 

Correction, I should have used the term Acute Oak Decline, of which the pathogen is still unidentified, instead of Sudden Oak Death, which is caused by P. ramorum, a pathogen not only attacking oaks, but many other tree species such as Larix and Rhododendron. Also see : this post.

Edited August 1, 2011 by Fungus

[sloth]

Fistulina hepatica only lives in/on Quercus robur (and Castanea sativa), because its mycelium needs the vinegar acids from the annual sap wood rings to grow inside outward before it starts producing mycotoxins, with which the cambium is killed, so it cannot be found on Q. rubra, as it lacks the necessary high concentration of vinegar acids (also see : Album Fistulina hepatica).

Besides, the mycelium of F. hepatica causes a bark necrosis, which is distinctly different from the buckling caused by L. sulphureus.

 

Thank you

[Bundle 2]

I wonder if this will meet with agreement- but I think Id have to say that here in the UK, we are taught that stems/boles which shows signs of reaction growth, similar to that which you illustrate Gerrit, are typically associated with a white rot ! It is interesting indeed that this should not be a conclusion we should rush to reach in light of what wee see and learn from your posts !

Good work. Fungi eh !

[Fungus]

that stems/boles which shows signs of reaction growth, similar to that which you illustrate, are typically associated with a white rot !

 

In oak, white rotters with selective delignification such as Ganoderma australe, predominantly change the flexibility/stiffness ratio to the extent, that the trunk becomes more flexible at the level of the central wood decay causing reaction wood to be formed, which shows itself as rather smooth barked local shell buckling ("life belts" or "love handles") on the outside, often accompagnied by (not yet visible) vertical shear cracks and lesions (torsion twist) on the inside. When white rotted oaks break and fall, unaffected parts of the trunk often stay behind as long pointed vertical remains of intact wood.

Brown rotters such as Laetiporus sulphureus, however, change the flexibility/stiffness ratio in such a way, that the trunk is confronted with a loss of stiffness and a local vertical weight overload because of demolition of the central wood column. Because of this, the reaction wood is pressed outside showing itself as extreme buckling zones with at first vertical cracks and later on horizontal cracks. In this phase, the tree becomes vulnerable of windthrow and when it falls, it breaks off almost completely horizontally without leaving much intact wood behind.

Edited August 2, 2011 by Fungus