A column of galls on the trunk of a large oak tree. The coloumn is between2 and 3 cm in height and consistes of a series of empty cones.
No interactions present.
These look like the empty sockets of Andricus quercuscorticis (agamic generation) galls to me.
Thanks Peter - I was wavering and came down on the wrong side of the fence.
Would you mind adding Andricus quercuscorticis as a revised identification, above (click on "Add a revision").
Entomologist and biological recorder
Lat/Lng: 51.9, -2.1
OS grid ref: SO9724