what i was suggesting is that, and certainly with Phytopthoras, is that the issues are in lost mycorrhizae associations and a lack of biodiversity within the soil food webs, along with changing climate causing range to be challenged for some species (north drift to cooler climes) leading to a more weakened stock of trees, trees just dont thrive without their associated organisms, especially the ecto-mycorrhizal associating Oaks, Beeches, Larches, Pines etc.
The Oak has the most diverse suite of host specific symbiont's in the British isles and saprobes etc, in a healthy system I believe these Oaks would not be falling foul of such issues as Phytopthoras.
Personally the biggest threat to the native oaks Q petrea and robur is hybridisation with Q. cerris and maybe other species of imported oak. I received some very special chited acorns from windsor to nurture recently, they come from an ancient English Q. robur and I have been very surprised by their leaf shape colour and stem being VERY red/wine coloured these are ancient genes of that i am certain, I am very much looking forward to seeing them grow on into fine trees.
one is destined for Hever castle, i have some other sites to find and a few to confirm for a home for each of these rare and majestic true english Oaks, I will take some photographs tommorow.
I havent seen these symptoms in any of the woods I visit in the south east of england (ancient woodland) and all the images I see are of forest timber silva situations contexts, this only re affirms my views on biodiversity and soil health being a key in tree health and vitality.