Catriona Bass reports:

NRN’s Botanical team had a fine botanising day on Sunday (23 June 2024), surveying the Playing Field's 'Carnival Meadow'. The survey was led by BBOWT’s Head of Ecology, Debbie Lewis. We had planned to survey some of the fragments of biodiversity left around Eynsham to record their existence in the face of increasing development, but we found ourselves chasing the topper with field after field gone under the tractor before we could survey their wildflowers. Hopefully we will catch them next year: there are hundreds of of Common Spotted and Early Marsh orchids in a field east of Siemens factory, rare greater butterfly orchids in another field, plus an unusual blue form of the stinking iris along the Wharf Stream Way. These urgently need to be documented and propagated before they vanish.



Common Spotted orchid (Dactylorhiza fuchsii) and Early Marsh orchid (Dactylorhiza incarnata) in a field near Siemens.

Photo Catriona Bass                       


Look out for the unusual Stinking Iris (Iris feotidissima) along the Wharf Stream Way 

Photo: Catriona Bass


The Carnival Meadow is showing well from the plants that we have all grown and planted out over the last three years. These have enhanced the original sowing of seed from Long Mead’s ancient floodplain wildflower meadow. However, the grasses are beginning to dominate somewhat. There are several reasons for this: the meadow needs to be cut before the Carnival, which means that many of the wildflowers have not yet set seed. This is a particular problem for yellow rattle, which is an annual and is called the 'meadow-maker' because is semi-parasitic on the grasses and so reduces their vigour, enabling the flowers to see more light.

We have lost almost all the yellow rattle. For the last two years the meadow has had to be mown at the end of June to accomodate the Fun Fair for 2 days and this is much too early for most of the yellow rattle to have set seed.  More concerning for the long-term health of the meadow, the farmer has been unable to make hay  as the meadow has been full of dog poo! This means that instead of the ripe wildflower seeds falling to the ground in the process of tossing and drying the hay, they get scooped up with the forage harvester and taken away, preventing the wildflower from spreading and giving the meadow species more resilience.

Please remind your dog-loving friends it is a hay meadow!

Happily, Hannah Shaw, our scribe, who is planning to study ecology at university next year, recorded 37 different species including the unusual rayed form of Common knapweed (which only exists in the Thames floodplain meadows), Devil’s bit scabious, the foodplant of the Marsh Fritillary butterfly, which is now extinct in Oxfordshire because of the rarity of  Devil's bit scabious. And we found the wonderful indicator species of these floodplain meadows – Great burnet, which can live for 100-200 years. Our survey thus showed that there has been an astonishing increase in biodiversity from its former grassy state, so all those who helped Carnival meadow come into existence and flourish, please take a bow.

Our huge thanks to Debbie Lewis for leading the survey - hopefully there will not be a test..?


The Thames’ valley’s unusual rayed form of Common Knapweed (Centaurea nigra).

Devil’s bit scabious (Succisa pratensis - the story goes that the devil was jealous of its beauty and bit off its roots - DBS is one of the few plants in a floodplain meadow to have very shallow roots)

Photos: Catriona Bass

We have two more survey sessions this summer (7th July and 11th  August, 2.00pm to 5.00pm) and we hope to continue next year. Led by Oxfordshire’s leading botanists (members of the Ashmolean Natural History Society of Oxfordshire), the surveys follow our NRN model of using local experts to help us record the rare bioversity where we all live while helping us improve our own skills for the future.


NRN’s botanical survey team identify the plants they have surveyed under the experienced eye of Debbie Lewis.

Photo Catriona Bass

If you’d like to become part of the botanical team, email Catriona on