Sycamores appear to be dying

[Stereo]

We've got many sycamores in our 5 acre wood and today I noticed that on many of them the leaves appear burned on certain limbs mainly lower in the tree. Many trees are affected young and old. Hope the pic comes out ok. Any ideas?

[Tony Croft aka hamadryad]

Sooty bark is a lethal disease of Acer pseudoplatanus. It is characterized by wilt, die-back, bark shedding and by the production of a thick layer of brownish black, dry phialospores in the bark by a fungus invading the cambium and phloem of affected trees. It has spread continuously in and around Wanstead Park, Essex, since 1945. The fungus has been identified as the North American species Coniosporium corticale Ell. & Ev., which is now made the type of a new genus Cryptostroma, because of characters of the stroma, conidiophores and conidia.

 

Conclusive evidence of pathogenicity is lacking, but there is strong circumstantial evidence that the fungus is an aggressive parasite. Preliminary inoculation experiments suggest that the fungus is normally spread by air-borne spores entering through wounds and broken ends of branches. The fungus appears to be a new introduction into England.

 

Copyright © 1951 British Mycological Society. Published by Elsevier Ltd All rights reserved.

[Tyz05]

We've got many sycamores in our 5 acre wood and today I noticed that on many of them the leaves appear burned on certain limbs mainly lower in the tree. Many trees are affected young and old. Hope the pic comes out ok. Any ideas?[ATTACH]96824[/ATTACH]

 

Was gonna ask the same thing this morning but you beet me to it! Got a few pics from our woods yesterday, some of the trees have lost nearly all leaves now though.

 

Excuse poor picture quality.

[daltontrees]

Could just about pass the first pic off as example of early Rhytisma acerinum but by 'eck the trees look pretty poorly from the other two pics. I have a vague recollection from my studies that C corticale is a "sapwood intact" saprophyte, up till then the only example ever cited was Piptoporus betulinus. I would go with the idea that it is present and dormant in the tree but is activated by stress. Again, vaguely I recall that the stress triggering activation can be prolonged warmth. But incessant f***ing rain? More likely to be drowning the roots than drying them out..! And providing ideal humidity for spore germination?

Strouts 'Diagnosis of Ill Health in Trees" reckins significance of C corticale is limited by the localised nature of the disease but I hope fpor all our sakes this year's abnormally dry start and then continual rain hasn't triggered a widespread outbreak of an incurable condition.

[Jesse]

Could just about pass the first pic off as example of early Rhytisma acerinum but by 'eck the trees look pretty poorly from the other two pics. I have a vague recollection from my studies that C corticale is a "sapwood intact" saprophyte, up till then the only example ever cited was Piptoporus betulinus. I would go with the idea that it is present and dormant in the tree but is activated by stress. Again, vaguely I recall that the stress triggering activation can be prolonged warmth. But incessant f***ing rain? More likely to be drowning the roots than drying them out..! And providing ideal humidity for spore germination?

Strouts 'Diagnosis of Ill Health in Trees" reckins significance of C corticale is limited by the localised nature of the disease but I hope fpor all our sakes this year's abnormally dry start and then continual rain hasn't triggered a widespread outbreak of an incurable condition.

It was the early spring drought trust me.

[Stereo]

Another pic.

 

[Jesse]

Another pic.

 

[ATTACH]96998[/ATTACH]

 

Yep as i said,

[Mick Stockbridge]

You're barking up the wrong tree. It's a Field Maple......

[daltontrees]

We had a baking three weeks up here at the end of March. Hasn't stopped raining since...

 

I will be sick Syc spotting for any scottish examples of this. Hope not!

[Big J]

Seen quite a few unhealthy looking sycamores out near us - leaves browning and wilting. Must be the constant rain.

[daltontrees]

I was bothered that those lesions didn't really look like Rhytisma, so I had a look at other Acer leaf lesions. I found this about Cristulariella depraedens -

 

"Lesions have light brown centers with darker margins and may have concentric zones of alternating light and dark tissue. In some cases, the lesions are nearly perfect circles, but in others they are irregular and may spread over entire leaves. Both fungi overwinter on remnants of leaves infected the previous year, and they begin to liberate spores in early spring. If conditions are favorable (cool and wet), infection of new leaves occurs readily, and subsequent generations of spores may be produced and cause disease throughout the summer. These diseases usually go unnoticed until early June when spots are numerous and badly infected leaves start to drop."

 

Forestry Commission lists it as one of the disorders of Sycamore. The timing and the "cool and wet" conditions seem to add up. Could this be a possible alternative explanation? If so the trees might be OK next year. Anyone got experience of this?