Some sort of rush?

Some sort of rush?

Observation - Some sort of rush?. Description: Abundant. Single stems in clumps. Florets part way up stem. Lots of cocoons of burnet moths attached (moths enjoying ragged robin). Ground dry when observed but presumably wet at other times ...? (Apologies rush tends to be background for photos - setting

Abundant. Single stems in clumps. Florets part way up stem. Lots of cocoons of burnet moths attached (moths enjoying ragged robin). Ground dry when observed but presumably wet at other times ...? (Apologies rush tends to be background for photos - setting off the orchids and burnet moths!)