Briza maxima Greater Quaking-grass DD I
The commonest quaking grass Briza media is a delightful little plant usually of limestone or chalky areas. Briza maxima has with larger flower heads, is the much less common Mediterranean immigrant and likely garden escape. Briza maxima is quite good enough for any dried flower arrangement - in fact it looks already dried in this photo.
It has successfully escaped into the countryside in the south of England but becomes significantly scarcer as you go north. There are few records in Scotland or Ireland.