Phytophthora canker?

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ddhlakebound

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Here's a bit of history. This Red Maple was planted by the homeowner in 1979 from bareroot stock. It sits in the border area between the yard and a brick paving stone patio.

It's elevated a few inches above the grade of the rest of the area, but a vacant lot drains directly into it's area.

Up until 1 or 2 years ago the patio area was basically a gravel parking area, so I'm sure it's pretty well compacted on the side of the tree with all the damage.

The homeowner installed the patio himself using no heavy equipment. He reported cutting or harming no large roots in the installation.

No other digging or trenching in the area ever.

Almost every branch on the damaged side of the tree is very heavy with samara, the side of the tree with healthy bark has very few samara, with a few branches being the exception and being as heavily seed laden as the injured side.

Leaves are somewhat small all over the tree.

Phytophthora is the most likely cause I can decipher, what do you think?

Is it too far gone to be managed in decline?

Would cambistat or mycorizihal (sp) fungi help enough to be of use?

Any other treatment options to keep it around for a few more years....or a decade?

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"the patio area was basically a gravel parking area, so I'm sure it's pretty well compacted ...
The homeowner installed the patio himself using no heavy equipment. He reported cutting or harming no large roots in the installation."

maybe he forgot...

"Phytophthora is the most likely cause I can decipher, what do you think?

Why? no lesions evident; just a big canker

"Is it too far gone to be managed in decline?

definitely not.

"Would cambistat... help enough to be of use?"

cambistat needs bark for uptake so no

"Any other treatment options to keep it around for a few more years....or a decade?

1. deflect runoff at property line or uphill in the vacant lot.

2. move patio blocks, excavate soil/gravel away from tree, esp. at edges of canker.

3. replace gravel with fertile soil, bioactive with mycorrhiizae, etc.

4. improve soil in rest of rootzone

ugly trunk; wood will rot in time so it is a race to grow that woundwood. if it rots a lot propping is an option. my guess is that the trunk was whacked long ago and the roots were so trashed on that side the tree could only respond feebly.
 
Phytophthora is a water mould which directly affects the ability of the tree to draw water from the soil. In Western Australia this has become our biggest killer of trees in National parks. Other than people of course.

I cannot see too well from your photograph but is the canopy in good condition? I ask because I have not seen a tree affected by Phytophthora cinnamomi that did not decline first on the canopy and then in the wood.
 
maybe he forgot...


Why? no lesions evident; just a big canker



1. deflect runoff at property line or uphill in the vacant lot.

2. move patio blocks, excavate soil/gravel away from tree, esp. at edges of canker.

3. replace gravel with fertile soil, bioactive with mycorrhiizae, etc.

4. improve soil in rest of rootzone

ugly trunk; wood will rot in time so it is a race to grow that woundwood. if it rots a lot propping is an option. my guess is that the trunk was whacked long ago and the roots were so trashed on that side the tree could only respond feebly.

Yeah, maybe he did. I questioned him pretty thoroughly about root damage and especially the process when he installed the patio. I'm sure lots of smaller roots were damaged.

The combination of him claiming no major root damage, the compacted soil and probable excess water due to poor drainage, and pics of similar looking cankers on maples labeled as phytophthora are what made me think of it as a possible/probable.

The gravel is no longer visible at all, but I think it's at least a couple feet away from the root flare. The patio is also set back a foot and a half or so from the flare.

Will do on the drainage deflection, mycorrhiizae, and soil improvement recommendations.

I struggled over the lack of evident lesions, but reasoned that the wounds were old enough that most visible evidence of the lesions could have disappeared. If it's "only" severe root stress that's causing the canker it seems much more possible to manage it for as long as possible.

Thanks for the help.
 
Phytophthora is a water mould which directly affects the ability of the tree to draw water from the soil. In Western Australia this has become our biggest killer of trees in National parks. Other than people of course.

I cannot see too well from your photograph but is the canopy in good condition? I ask because I have not seen a tree affected by Phytophthora cinnamomi that did not decline first on the canopy and then in the wood.

The canopy is in fair condition. Leaf color is close to matching nearby red maples, may be just a tad lighter in color. Leaf size is somewhat small. Coverage throughout the canopy is good, and no branches have any tip die back on either side (damaged and undamaged) The samara distribution is very odd, the damaged side very heavy, the undamaged side light, but a few limbs on the undamaged side as heavy with samara as the damaged side.
 
Where to buy your mycorrhizal fungi, (for a fair price, and receive a quality product)?

Any special concerns in the application?
 
Any particular species?

Here if the disease affects the crown then it is pretty l.ate to treat.

Phytophthora cinnamomi is the species most discussed Guy but I am at the very beginning of a steep learning curve. Someone with your smarts would get good info from this website.

http://www.cpsm.murdoch.edu.au/

And if you are up for a brain bursting chat you could email Giles Hardy.

http://www.treehealth.murdoch.edu.au/html/experts/GHardy.html

He is the most knowledgable person that I know of in WA regarding this pest. He has a massive work and correspondance load and still responds to email. Seems like a nice bloke.
 

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