What's causing this on Poplar?

[Stephen Blair]

Out walking this morning and noticed this on nearly every Poplar in the stand.

  For some reason I've got a kind wasp damage of some kind in my head, maybe I read something on here.

thanks 

[Stere]

Bacterial or fungal canker?

[openspaceman]

Yes looks like the cankers have exposed the wood and let Fomes fomentarius in

[Squaredy]

40 minutes ago, Stephen Blair said:

Out walking this morning and noticed this on nearly every Poplar in the stand.

  For some reason I've got a kind wasp damage of some kind in my head, maybe I read something on here.

thanks 

Wonderful habitat.  Awful crop.  Not sure it looks very safe either.  Is it your stand of Poplar?  If it were mine I would be thinking about felling and finding something that suits the situation better as clearly those trees are not doing well.

[Stephen Blair]

Not mine, I wish I had land and trees.

  Public pathway runs through them so a concern.