Looks like maple tar spot. https://hort.extension.wisc.edu/articles/tar-spot/

Thanks. That does look like it. I appreciate the reply.

And those in the pictures are not 'Red Maples' (Acer rubrum).

Could they possibly be Acer platinoids (Norway maple)?

Appears to be a sugar maple, and I'm thinking the disease is probably Phyllosticta leaf spot rather than tar spot.

@arbordave (SE MI), I appreciate the reply. Is there a systemic treatment I can use next spring/summer to help prevent this from happening?

Here is some information on the subject:

https://extension.okstate.edu/programs/digital-diagnostics/plant-diseases/phyllosticta-leaf-spot-of-ornamentals.html

Neither of the two leaf spots mentioned is particularly harmful to the tree, both being more a cosmetic/aesthetic issue. So treatment is optional and generally not required. And since the spores of both can overwinter on fallen leaves, raking and disposal of all leaves will go a long way in retarding their development next season.

And I am not convinced about the phyllosticta :-))

Reading about it and I see that raking leaves and disposing of them is mentioned. I live in a heavily wooded property and it's not really practical to do that.

This happens to my sugar maples every year to varying extent in late summer/early fall. Really nothing you can do, and tho somewhat unsightly, doesn't really hurt the tree.

there is no need to 'treat' deciduous trees in october ..

and since both are surface diseases of leaves.. i highly doubt there would be any systemic [interior] control ... but i could be very wrong with that ...

you dont mention.. or i missed.. . where you are.. is this an endemic problem in your area.. you should probably contact your COUNTY extension office for some local guidance ... and then report back to us .....

ken