What insects are causing this damage on my oak?

[guimeixen]

I've had this oak for some years, but never had these issues, so maybe someone can enlighten me on what is causing this. It's two different problems, but I don't know if it's two different causes or not.
There's damage on the leaves and on some new buds that were opening.

The image below shows the first problem. The leaves become yellow and the veins remain green.
Below them, I see some tiny insects moving around. I increased the contrast on the other images for them to be more visible.





The second problem is with the opening new buds. Recently it had another growth flush and everything grew well and healthy except on three or four buds that started growing later.
One of them opened, but the leaves came out with dark areas in them. The other barely grew and the tiny leaves are filled with those dark areas.
When I tried to separate some of the leaves to see if there was anything in there, I saw a tiny larva in one of them.

 

[leatherback]

looks like mildew to me.

 

[Potawatomi13]

Spray well with insecticidal soap and can use a daconil spray if you have mildew. Don't do this in hot sunny conditions.

 

[leatherback]

ah shoop. Now on a large screen.. Spider mites too. Treat with a spray, three reps minimum with 4-6 day interval.

 

[guimeixen]

With mildew you're referring to downy mildew? Those circular yellow spots?
I do treat it for powdery mildew, but it's the first time that one shows up.
I do have some sprays that I will try.

What about the second issue with the buds opening with those almost black leaves?

 

[Adamski77]

The buds situation... I had this on my oaks and I attributed this to the sun exposure (too much)... moved them in the shade and it improved dramatically...

 

[guimeixen]

The buds situation... I had this on my oaks and I attributed this to the sun exposure (too much)... moved them in the shade and it improved dramatically...

I don't think it's that, it has long healthy extensions and they have been in the sun and they are a normal green, no problem at all. From what I've seen this was on only four buds. I don't think there is more. On one of them I saw a tiny larva/worm like thing in the middle of the leaves.