Found yesterday.
Kuehneola uredinis – Bramble Stem Rust, appearing locally in great profusion.
Click on images to view at full size.

[attachment=2]Kuehneola uredinis – Bramble Stem Rust(1).jpg[/attachment]Close-up of uredosori on affected stem.

[attachment=1]Kuehneola uredinis Spores x400.jpg[/attachment]Uredospores x400.

[attachment=0]Kuehneola uredinis Spores x400 Measured.jpg[/attachment]Uredospores x400 with Annotated Measurements.
Regards,
Mike.