An expanse of grass but a particular kind. This is Portholme Meadow between Huntingdon and Godmanchester in Cambridgeshire, an alluvial flood plain still managed as a Lammas hay meadow. I went in search of a rare species in a rare habitat.

 Snake's Head Fritillary (Fritillaria meleagris) grows in meadows that flood in winter and drain in summer. I read they can be found on Portholme but finding them among two hundred and sixty acres of grass was not easy.

 I was alerted to their location when I spotted a chap in the distance wearing fluorescent cycling gear lying flat on the ground taking photos. As I approached I perceived a patch of Fritillaries dotted around one of the marshier areas in the heart of the meadow.    

  Typically the drooping flowers are burgundy red with a distinctive checkered pattern. Specimens of pure white provide a striking counterpoint. F. meleagris grows from a bulb and it's worth trying them in the garden but they need a very moist soil to flourish. Wild colonies persist in a few places. They may be native to this island or perhaps an ancient introduction, no-one really knows

 The meadows of Magdalen College, Oxford are smaller than Portholme but renowned for Fritillaries in their thousands [see entry dated 17th. April 2017]. I note that both are enclosed by rivers that run right round them hence their tendency to flood. 

 Whilst researching this topic I was struck by the fact that Portholme now represents seven per cent of the total area of alluvial flood meadow in the UK. Unimproved lowland hay meadows are few and far between.

 So I was very happy to see these Fritillaries in their natural habitat. Obligingly the sun broke through and illuminated the scene.