On 03/10/2020 23:52, Jon Nicoll wrote:
Hi All
I'm trying to determine why our viburnam has died, in somewhat spectacular fashion

This viburnam was probably 30+ years old. It had three or four main trunks coming from a single crown. We live on the South Coast of the UK.

The tree has mostly seemed healthy, although I had previously noticed that one of the smaller trunks appeared poorly. Also some of the upper smaller branched appeared to have died. However a couple of months ago I tugged on one of the smaller main trunks, and it came away at the base!

A week or so ago the whole tree fell down - luckily no damage done. It has a rose bush intertwined with it and that may have cushioned the fall somewhat. It has been fairly windy here, but not extremely so.

I am concerned to find out whether it is something like Honey Fungus (don't think so), some other fungus, or something else that has caused this death. Understanding this will obviously affect what I replace it with, and what I do to the remaining crown etc.

I have taken several pictures, these can be seen he

http://images.jkn.webfactional.com/viburnam

My main observations a

- Most of the wood of the crown, and the lower part of most of the main trunks, have gone 'spongy'. One of the photos shows a cross-section of a good branch next to that of the crown
- From some tapping at the main roots I think that at least some of them are similarly spongy, with the rest of the roots seeming to be sound
- You can see that there are some good-looking shoots coming from around the crown
- There is evidence of slight fungal growth - some white lacy areas. But I cannot see any fungal rhizomes or anything like that
- There are a couple of ?cankers? or ?Galls?, looking like the top of a mushroom, but 'woody'. The largest of these is about 4" across. I have taken a photo of this separately
- There are deep cracks running up one or two the trunks
- This my or may not be relevant but if you get close to the closely there is a slight fecal smell. I had noticed this before in wet weather but since we have put horse manure down (for the nearby rose), and there are also drains running near, have not paid it any attention before. I have read about some pests who cause such a smell though
- I did see a fair few wood-louse type creatures crawling around the crown. I think they are just living off the rotting wood though, rather than causing the problem. No other obvious insect infestation
- Most of the leaves were healthy; perhaps a few have been a bit deformed. No major 'being eaten' damage that I can see.

I did wonder if this is just waterlogging - the crown has a bit of a hole in it, and the tree was a bit top-heavy with the branches swaying in the wind.

Thanks for any thoughts and insights!

Jon N

Looks like my plum trees. Every year I find the latest fungus on some
stem or other with the wood above it dead and rotting, lop it off, and
it grows back from the base again.

When I bought the house in 93 there was a cut down greengage stump. Now
its bearing lots of fruit and is 20ft tall.

Fungus eats trees. There must be a hundred plus species...yeah I had
honey fungus at one point but I cut down all the trees in that part if
the garden and it never reappeared.

Now I have three shaggy inkcaps in an isolated piece of lawn that has
never ever had any fungi before. No, I don't understand it, either.
But butter bacon fat and garlic are waiting for them when they are old
enough and big enough...

I think you get fungus if the bark gets damaged in any way, and once
there, if its the right sort it just kills everything by tapping into
the sap bearing channels. So roots survive, but anything above the
fungus does not.

If the root is healthy it might be worth leaving it to produce new shoots.


--
I would rather have questions that cannot be answered...
....than to have answers that cannot be questioned

Richard Feynman