Robin's Pincushion or .... the Bedeguar gall

Diplolepis rosae

This is a spectacular gall and quite commonly seen on Dog Rose hedging. Colouration can vary from green to brilliant scarlet and eventually degenerates to rusty brown.

Appearing in late summer and autumn on wild rose bushes, these unusual growths are created by the tiny wasp Diplolepis rosae. The grubs inside feed on the plant through the winter and emerge in spring. The cushion provides a home to many other tiny creatures. It's sometimes called the Bedeguar Gall.