Swelling on stems - covered in white fluffy material
No interactions present.
I photographed the same thing here in Martin today and was going to put it on hoping for an ID. Still hoping!
Hampshire Dragonfly recorder
Hampshire & IOW Wildlfe Trust
Could this be wooly aphid attack?
The hosts are listed as Horse Chestnut,Lime,and Maple.
I think that there are related species, which might be more interested in Pyrocantha; and of course these creatures may not be as host-specific as the books say.
Can't really tell from the photos if this is horse chestnut scale insect, but if it is it is not currently considered to be a gall causer. Some scale insects are, some are not. The white material is a waxy secretion as produced by many scale insects.
Lat/Lng: 53.7, -2.7
OS grid ref: SD5926