It helps to know where you are gardening and this tree is growing. City/state is typically sufficient.

That looks like classic oak anthracnose. Have you had a wet summer, or a spell of wet weather leading up to this observation?

North of toronto canada Z5

cool wet summer

Let's see if others from northern climes weigh in, but I'd expect that kind of result after plenty of wet weather.

Oak anthracnose is not pretty, but I don't think it is much more than an aesthetic insult at this stage of the growing season. As long as other elements of its environment are within normal ranges ( soil pH, fertility, etc.), it should be OK for the long term.

one of the cooler wetter summers we've had in a while.

what's that oak disease that's causing serious concerns?

im not much impressed by leaf damage in what is basically september...

the tree and its leaves are tired from every insult they have suffered since they emerged in may ...

inside 4 to 6 weeks.. they will all be on the ground.. and you will be cleaning them up.. in bad years.. they can even go down early.. perhaps starting around.. wait for it.. 9/1 ..

sorry i dont know the metric conversions for dates.. lol

ken

Ken, it's looked shoddy since early July.. maybe earlier.. just haven't gotten around to bringing it up here.. From a distance, tree looks full and green and healthy..

???

Whats t373???