ID help on Kanzan symptoms

[Mr Fir]

I have followed 'Diagnosis of ill-health in trees' by Strouts and Winters but didn't get a definitive answer...maybe you can help?

 

Here's my data:

 

• Prunus Kanzan
  
• Back garden, grass around. Path 3m to W. Unaltered RZ
  
• Mature? 50-60yrs
  
• Has had pruning over the years, some for low branches and some for die back - not done during optimal summer time
  
• Good fertile soil on top of sand base 3ft down
  

 

Symptoms

• Die back in upper crown (pic 1), spreading
  
• Late flowering on sparse areas in upper crown, small leaves
  
• Leaf discolouration (pic 2 - left leaf is normal) - Autumn effects? Seems localised to upper crown
  
• Cracks on lower stem to 1.8m (pic 3)
  
• Some bleeding
  
• Some frass at base of 1 larger (pic 5)
  
• Bulging and flattening on all lower stems
  
• Mallet suggests altered wood
  

There is a stump of a removed Ash about 3m away that has prolific Kretschmeria/ Ustulina deusta and a large unidentified bracket fungus.

 

Seat of damage - Roots or root collar, water conducting wood

 

Suggested diagnosis'

Silverleaf (pruning wounds, leaf discolouration - no fruiting bodies identified)

Bacterial canker

Cherry bark tortrix

Internal decay from ...?

 

Well that's about as much as i've got so far, if anyone has a thought on what it could be or something else to look for i would appreciate the help.

[Tony Croft aka hamadryad]

that cherry is growing at a rate of knots, at least in increment, I reckon its in too good a health to be silverleaf or Chondrostereum purpureum, i suspect as with many old kanzans this will have an as yet unfruited ganoderma. this would explain the rapid secondary thickening going on.

 

foliage is probably just drought its been a tough year for shallow rooters

[Mr Fir]

Cheers for the input, true about the secondary thickening. Could the cracks be a response to internal decay? Sounded like it ascended quite high. Vigour has deteriorated the past 2-3 years, leaves and flowering have been consistantly poor on affected areas the past few years too...altered xylem?

[Tony Croft aka hamadryad]

Ganoderma australe, just from your description, I bet its cored out with an intense white rot, and mycelial sheets are forming in the the limb unions eventually pushing them apart

[Fungus]

Ganoderma australe, just from your description, I bet its cored out with an intense white rot with selective delignification, and mycelial sheets are forming in the the limb unions eventually pushing them apart

 

I would sooner expect this to be caused by the intense simultaneous white rot of the mycelium of Phellinus tuberculosus.

[Tony Croft aka hamadryad]

I would sooner expect this to be caused by the intense simultaneous white rot of the mycelium of Phellinus tuberculosus.

 

not on kanzans here in the u.k, thats mainly confined to prunus pissardii

[Mr Fir]

Interesting diagnosis from both of you, thanks. Would a generic 'intense white rot' suffice for recomendations perhaps? Is there some way I could find out either way? I'm interested myself...

[Tony Croft aka hamadryad]

Interesting diagnosis from both of you, thanks. Would a generic 'intense white rot' suffice for recomendations perhaps? Is there some way I could find out either way? I'm interested myself...

 

I would say give it a tickle of a reduction and see how it goes, it certainly is vigorous

[Mr Fir]

I got a cutting from high up and also was looking at lower shoots today. Very small amount of growth the past 5 or so years, 3-5cm normal, 8cm max...

 

Although I told the owner how to see the annual growth between scars he wasn't convinced and almost convinced me that some looked like a double flush: how likely would that be on Prunus and really, a few years in a row?

 

I think vigour is poor, energy is being used supporting a decaying lower stem and so the upper crown is struggling.

 

My recomendation so far is to put mulch mat and mulch to radius of 2-3m, small amount of slow release fertiliser and a slight crown reduction in the summer if vigour is looking better to stabilise the compression fork and decay problem. Also to tell the owner not to prune it outwith optimal mid summer.

 

Thanks for the input, any more is welcome