No interactions present.
... which has terminal infloresences. It might be Frangula alnus with immature berries.
Perhaps, it was growing in the vicinity of other Buckthorn but in those the grooves in the leaves led to the tip, characteristically; so I'm not sure.
... but Rhamnus cathartica has veins which are swept forwards towards the leaf apex (as in Cornus and Philadelphus) while Frangula alnus has the commoner "herringbone" venation pattern.
Frangula has leaves with entire edges (as in this case) whereas in Rhamnus they are serrate.
Lat/Lng: 52.311819, 0.28884
OS grid ref: TL561706