lice on oak leaves

[ten oaks]

Hi,am new on the site, i am desperately looking for a natural pesticide to save my oak trees,about ten 50 year olds, i live in portugal and was sold a chemical, to be sprayed,some pretty nasty stuff, and before i do all my trees with that,(if i dont fall out...) hoping that maybe there is a friendlier alternative.

the leaves are becoming transparent,one can almost see through them,displaying the nerves against the sky.The guy in the shop said that it starts with the leaves being covered with a whitish ´´film´´, for want of a better word.(this seems strange as it is a lice-louse?)English is not my native language.

I am gonna start with the chemical anyway, it seems i have no time to loose, some trees are already 50 pct affected,but still hoping for a better alternative.
Gonna cost me some braincells,the few i have left...

 

[ch woodchuck]

Are they cork oaks?,or some other specie.If you know the specie it may be easier to find the pests of that tree.

 

[ten oaks]

no cork oaks

thanks,not cork oak trees, apparently the females get affected earlier,males much less affected.

someone told me whey from milk may do the trick, gonna try that but on a few trees only, will try upload some fotos next time, had a crazy week,hence late reply

boas...ten oaks