amateur concerned about chestnut tree
I don't know much about biology or chestnut trees, so I can't give very much info about the tree (what it's called and things like that). I currently live in Poland, some 150km from the coast in a region called Kaszube where there are lots of lakes and rivers. In our court yard we have a chestnut tree standing next to the riverbank. I'm a little concerned on its behalf because of the small brown blemishes that have started to appear on the leaves. I can scrape the blemishes off, they are like flakes, and underneath I find a black or dark tarnish. Is the tree unwell or are they just "tree freckles" from the sun? Can I or should I do anything about it?
Thank you - I will appreciate any input and advice.