Looks like Cichorium, but it didn't seem the right flower arrangement for C.intybus.
No interactions present.
I think your right on this ID Tim. Initially I thought it was Chicory, but then when I looked closer, the flowers were not arranged on the stem in clusters like C.intybus. Having looked at on line photos of Cicerbita macrophylla, it definitely looks the same. The National Trust are 're-wilding' the estate to encourage wildlife, these were growing at the edge of a tree canopy in long grass.
PDSell Watsonia 16:121 9186)
other possibilites are...
plant glabrous = plumeri
no glandular hairs on stem/peduncles = bourgaei
Lat/Lng: 51.30923, -1.09513
OS grid ref: SU631570