Thoughts on weeping willow failure

[Andyd1606]

Hi all I had a phone call yesterday morning from a regular customer saying their weeping willow had lost a branch!!

On going over to look at the tree at least 50% of it was lying on the floor of the garden.

It seems to have failed at the union of the two main stems causing one to split and tear away.

The tree generally appears in good health there are no signs of decline in the crown. I had a look around the base of the tree and surrounding area and can't see any visible signs of fungai.

The only thing of note is a white powdery mould like substance on the inside of the tree and the tear see pics. Any ideas what this is or could there have just been a weakness in the union causing the failure.

Sorry there's not a pic of the whole tree it's fairly large and I couldn't get it all in focus.

Thanks any ideas gratefully appreciated

Andy:001_smile:

Edited July 20, 2014 by Andyd1606

[Andyd1606]

 

 

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[Marc]

Survival strategy? Like a Mulberry possibly.

[Chris at eden]

Its a co-dominant stem failure. The equal size of both leaders means there are no over lapping fibres to keep the branch in place when loaded. Normal branches are enclosed by the larger trunk material. This one also has a lean which introduces a static load into the fork and increases the effect of dynamic loading from the weather. You can actually see how the branch has twisted as it came down giving an indication of the load. Was there heavy rain when it failed?

[Andyd1606]

Thanks I did wonder if it was just a failure as there was nothing else I could come up with that had caused it. Yeah it was raining heavily Sat night was blowing a bit of a storm for a few hours. Both stems are fairly substantial and have a large crown so plenty of weight on them

 

 

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[Chris at eden]

Survival strategy? Like a Mulberry possibly.

 

I see where you are coming from but I don't personally think so or if it is not a very good one. The shedding of small diameter braches in winds to save the tree yes. But this is half the tree and has left a large wound that will never occlude in a soft wooded tree. This tree is doomed sooner or later.

[David Humphries]

the "white powdery mould like substance" could be the mycelium of Laetiporus sulphureus a common brown rot decayer of willow.

 

 

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[daltontrees]

Its a co-dominant stem failure. The equal size of both leaders means there are no over lapping fibres to keep the branch in place when loaded. Normal branches are enclosed by the larger trunk material. This one also has a lean which introduces a static load into the fork and increases the effect of dynamic loading from the weather. You can actually see how the branch has twisted as it came down giving an indication of the load. Was there heavy rain when it failed?

 

Are you thinking it exhibits some of the signs of summer branch drop?

[daltontrees]

the "white powdery mould like substance" could be the mycelium of Laetiporus sulphureus a common brown rot decayer of willow.

 

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Interesting! The fork looks like it was intact until failure, and the 'mould' must surely have come from within. Do you think the brown wood at the centre of the stem is consistent with rising internal decay? Since you pointed it out to me a couple of years ago, I have been noticing that L.s seems readily to exploit internal cracks in Willow from the bottom up with little or no aeration.

[Marc]

I see where you are coming from but I don't personally think so or if it is not a very good one. The shedding of small diameter braches in winds to save the tree yes. But this is half the tree and has left a large wound that will never occlude in a soft wooded tree. This tree is doomed sooner or later.

 

Willow doomed because of tear outs and exposed tissue? Nature is never very subtle, often why we can sometimes prevent this from happening in the urban environment by shortening lever arms. Still looks to me like self optimisation along with all other suggestions here.