Identification: Japanese maple potential disease identification

Can anyone help identify this marking on my 10 yr old seiryu?

I recently pruned this branch (pic attached) because it was problematic to growth, but there is another branch still on the tree with similar spotting and still showing new growth.

 

Hello Joseph,

It's just a guess, but it looks like mechanical damage followed by bacterial entry causing the blackening. Hard to say what might have caused the damage, might be birds of some sort. Not much to go on.

You can treat the bacterial issues with copper pulverization, if the injured branches are shaded they should be able to heal over the course of the summer season.

HTH, Emery

 

Same opinion: we can see some sort of parralel scars in particular at the bottom of the branch.

 

That makes sense. I acquired the tree from a site that may have been trimmed with poorly cleaned tools. Thank you very much for your replies. I feel very supported. :)

 

Did Chicago area have cicada last year? Looks remarkably similar to damage I saw from cicada in Iowa in 2007