We also call it Blister gall.
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Carol. No-one has been. No-one has taken the time to say no it's obviously Taphrina tosquinetii.
But it isn't (obviously, I mean) I think you might be right with the ID. You add "we also call it Blister gall". I don't think it's that.
Eriophyes brevitarsus is caused by a mite and doesn't normally cause normal-looking blisters but subtly different growths - see http://www.naturespot.org.uk/species/acalitus-brevitarsus.
The underside of the galls are usually the most useful for ID but here it's not entirely clear. See mine http://www.ispotnature.org/node/437618 and this http://www.ispotnature.org/node/286924
I will reserve my agreement until you respond.
It's a poor show that this post has had NO attention.
If you ever get really jaded, then Edit posts and add a picture or a word, then Save. This puts up a New flag and some people watch for those.
As you can see Derek I have put it on as both and no response, I am interested in anything we find as we walk, I like to ID them or have them ID, I use Redfern & Shirley's British Plant Galls as my reference, if you wish to add an ID please do I am only interested in naming our finds :)
Lat/Lng: 53.629722595215, -2.6464869976044
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