Gall of the week is the bloodwood apple, found in Australia, caused by scale insects in the genus Cystococcus on bush coconut, Corymbia opaca. Both the gall and the larva inside are 'bush tucker' food apparently.
Photographer not known.

Gall of the week, a cynipid wasp gall on roses in Canada. Details in the caption.
Photo by Peter Shirley.

Gall of the week, this is a good time to find the rust fungus, Puccinia smyrnii, gall on Alexanders, Smyrnium olusatrum.
Photographer unknown.

Gall of the week, one to find on a coastal visit, is caused by the mite Aceria hippophaena on sea buckthorn, Hippophae rhamnoides.
Photo by Steve McWilliam.

Gall of the week is caused by a cynipid wasp, either Diplolepis nervosa (spiked pea gall) or D. eglanteriae (smooth pea gall). Without spikes they cannot be separated as D. nervosa can occur without them. They are now recorded on iRecord and iNaturalist as D. eglanteriae agg.

Galls of the week are marble galls of one or more species of cynipid wasp causing marble galls on oaks, Quercus spp. How many can you count with exit holes?
Origin of this photo unknown, if you do please let us know.

Gall of the week, well galler, or to be precise cecidologist, of the week is Alfred Kinsey. Before becoming famous for his work on human sexuality in the 1940s, Kinsey was a leading authority on cynipid wasps, with many publications and a collection of over five million of them.

Gall of the week, an unusual one, is caused by a fungus on a fungus. It is Agamothyia wankowiczii on the bracket fungus Ganoderma applanatum.
Photo by Graham Calow.

Gall of the week is caused by the cynipid wasp Pediaspis aceris on sycamores, Acer spp. A recent arrival in the UK.
Photo by Stephane Claerebout from bladmineerders.nl

Gall of the week is that caused by the gall midge Rabdophaga salicis on willows, Salix spp.
Photo by Peter Shirley.

Gall of the week is caused by a recently discovered species new to Britain, the gall wasp Andricus coriarius f. agamic on oak, Quercus robur.
Discovered and photographed by Maria Fremlin.

Gall of the week is caused by the cynipid wasp Andricus quercuscorticis f. agamic on oaks, Quercus spp.
Photos by Graham Callow.

Gall of the week, with its causer, is that of the tephritid (picture wing) fly Urophora cardui on thistles Cirsium spp.
Brilliant photo of the insect by Malcolm Storey, gall photo unknown source.

Gall of the week, with a bonus small copper butterfly, is caused by the midge Dasineura kiefferiana on rosebay willowherb, Chamerion angustifolium.
Photo by Mike Poulton.

Gall of the week, can be found all year round, is caused by the gall midge Taxomyia taxi on yew, Taxus baccata. This is the second year gall, more often found than its smaller counterpart, the one year gall.
Photographer unknown.

Gall of the week is that of the midge Contarinia nicolayi on hogweed, Heracleum sphondylium. With a name like that perhaps we should call it Santa's gall.
Photo by Peter Shirley

Thanks for following, best wishes and good galling in 2026.

Renamed a few years ago.

Gall of the week is one you may be bringing into your home this week. It is the gall of the aphid Sacciphantes viridis on Norway spruce, Picea abies.
Photographer unknown.

Gall of the week is that of the cynipid wasp Aylax papaver on poppies, Papaver spp. An ungalled seedhead is included.
Photo by Peter Shirley

Gall of the week is caused by the cynipid wasp Cynips longiventris f. agamic on oaks, Quercus spp.
Photo by Peter Shirley

Gall of the week is caused by the gall midge Iteomyia capreae on willows, Salix spp.
Photographer Peter Shirley.

Gall of the week is that of the sawfly Blennocampa phyllocolpa on roses Rosa spp.
Photo by Tom Higginbottom on Bladmineerders.nl

Gall of the week is the nail gall of the mite Eriophyes tiliae on lime trees Tilia spp.
Photo by Mike Poulton.

Yes indeed.

Gall of the week, usually found in leaf axil buds, is caused by the cynipid Andricus glandulae f. agamic. On oaks, Quercus spp.
Photo by Peter Shirley

Gall of the week is that of the curiously two-chambered one of the cynipid wasp Cynips disticha f. agamic on oaks, Quercus spp.
Photos by Malcolm Storey.

Gall of the week is caused by the fungus Taphrina tosquinetii on alder, Alnus glutinosa.
Photographer unknown.

Still in Ohio, gall of the week is a leaf gall on white swamp oak, Quercus bicolor. Seems to be Neuroterus quercusverrucarum, the oak flake gall. Is this correct @gallformers?
Photo by Peter Shirley.

Yes it does (and not only the hybrid), in fact three species of the aphid genus Pemphigus occur on the petioles of P. nigra and its hybrids’

Gall of the week: Galling is in Ohio USA, and came across this. Seems to be a rough oak bulletgall caused by the cynipid wasp Disholcaspis quercusmamma on swamp white oak, Quercus bicolor. Happy to be corrected.
Photo by Peter Shirley.