Caterpillars on small Silver Birch tree.
No interactions present.
See one of the images at
Thanks for pointing the direction on these. I never even remotely thought of sawflies or anything other than moth caterpillars.
Will have to widen my horizons at some stage but still an awful lot of learning about moths to do before I start thinking seriously about that.
Lat/Lng: 52.246189700093, -1.775289773941
OS grid ref: SP154609
The location is close to overgrown paddocks previously grazed by horses