Nine Oaks ~ HELP !

[zoed73]

I'd appreciate some help with a problem with some of my 9 "Oaklings" which have grown from acorns in plant pots. I presume they all came from the same parent tree as I grabbed a handful of acorns from the several hundred lying beneath the same magnificent Oak. (in Oct/Nov 2006)

As with last "summer" there is a problem again this year. I won't attempt to explain, instead here's a photo which should show it. This is affecting 5 out of the 9 trees.



It (presumably a fungal problem?) only seems to affect the upper group of leaves. Here is a photo of the lower leaves on the same tree >



What is the infection? ~ and is there anything that I can treat the trees with?
~ or do I not have to do anything?
Although this happened last year, none of the trees seemed to have suffered as a result.

Any help appreciated, thanks.

[zoed73]

So ~ there's no-one here on the forum who knows about Oaks ? ? ?

[djackso]

Oak mildew

Biotic factor that contributes to oak decline

Powdery mildew of oak is caused by the fungus Erysiphe alphitoides (also known as Microsphaera alphitoides) and it is a common foliar pathogen of oak throughout Europe. First found in England in 1908, it was considered a contributory factor in the oak dieback episode the 1920s.

Erysiphe attacks young leaves and soft shoots, covering them with a felty-white mycelium, causing them to shrivel and blacken. Mild overcast conditions are optimal for development of the disease, which usually appears in summer when warmer conditions prevail.

You could Google some picks and see if this is it.
Sorry I can't help more.

[zoed73]

Thanks djackso for your response ~ that gives me a bit of a springboard.