Puccinia urticata var. urticae-hirtae

Uredinia and telia on Hairy Sedge (Carex hirta).  Puccinia urticae-hirtae is part of a wider Puccinia urticata s.lat. species complex with the alternate aecial stage on Nettle and the primary uredinial and telial stages on various species of sedge.   

The uredinial and telial stages of other species or varieties within the overall Puccinia urticata complex; identification is dependant on host species of Carex  

host

Photograph the rust on the host. Microscopic examination may be needed. Ensure you have noted the host-plant species in your comments

Hairy Sedge (Carex hirta) /Nettle (Urtica dioica)

In some sources, this species is considered a variety within the Puccinia urticata complex of species  see Plant Parasites of Europe account