On trunk of mature sycamore.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
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This looks rather like one I've found, which I thought might be Ramalina fastigiata. But I may well be totally wrong. The ones I've found that I thought were Physcia were overall flatter than this, and the whiskery black-tipped hairs were quite easy to see (but maybe they are visible closer up?)
I think the bottom right hand corner of your photo does look like Physcia - I can see the whiskery hairs - but I suspect that the big tufty bit in the middle is a different lichen (maybe Ramalina). Hopefully someone more knowledgeable will have a look!
Thanks for IDs and comments. I find these two very difficult to distinguish. I wasn't even sure they were different, I thought the shorter ones might have just been less mature. The ones you have identified as Physcia were very abundant on all of the four trees I looked at and all pretty short. The Ramalina were quite a bit longer and distributed much more sparsely, usually higher up the trunk where it's difficult for a shortie like me to get a good look - photos taken by holding camera at arm's length and shooting hopefully!
Lat/Lng: 50.606, -2.465
OS grid ref: SY671785
On one of a group of mature sycamores on the edge of a sportsfield