Cambridgeshire rarities

A Lizard Orchid, Himantoglossum hircinum, on the Devil's Dyke.

An overnight visit to Cambridgeshire gave the opportunity yesterday to spend the evening out botanizing with Dr Alan Leslie, who is preparing a new Flora of Cambridgeshire and is intimately acquainted with the county's plants. Our destination was the Devil's Dyke, or Ditch, where it runs over Newmarket Heath. It's a Saxon chalk rampart with associated ditch, evidently originally intended to control access in and out of East Anglia beyond, but now forms a linear island of fascinating vegetation across the agricultural landscape and the racecourse. It has been frequented by Cambridge botanists for centuries, and is well known as an important site for several nationally rare plants, but new species  are being recorded there all the time. Here are a few of the special plants we saw: the Lizard Orchid was the first I had seen in Britain, so a very exciting plant for me.


Fruiting heads of Pulsatilla vulgaris on the dyke: both it and the Lizard Orchid have been known here for centuries.

 

Much less spectacular; the tiny flowers of Bastard-toadflax, Thesium humifusum, the only member of the Sandalwood family (Santalaceae) to grow in Britain. It is a hemiparasite.

The native British form of Sainfoin, Onobrychis viciifolia.

Rosa × dumalis, the hybrid between Rosa canina and R. caesia.

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The occurrence of Geranium sanguineum on the dyke is extraordinary, being very distant from any other native population.

Today's extreme rarity: Fen Ragwort, Senecio paludosus

The only native site for Senecio paludosus - a couple of square yards of ditch by the side of a busy road.