I promised yesterday, I would reveal the identity of the horror teddy bear in the picture. Henri Brocklebank gave the right answer and maybe others knew that is what remains of a bedeguar, a gall also known as ronin's pincushion, a bright red mossy thing with sticky filaments that grows on wild rose bushes. During the winter the red filaments are lost and te knobbly brown, chambered husk remains. The black holes are where the gall causing wasps or their inquilines or their parasites have escaped. The gall causing wasp is Diplolepis rosae, but many other micro-wasp species and their parasites and hyperparasites live within the gall, some killing the original gall former.
I have also found a few old ram's-horn galls, Andricus aries on the same GSM3 oak tree that hosted the bedeguar: young oaks often seem more susceptible than older examples. The ram's-horns turn black in winter after the gall causer has flown making them rather more visible that when they were green.
