Nature Notes - Danish Scurvy Grass by Ian Brand

As a cyclist, I have been out daily, just cycling locally during this dreadful pandemic, where I am also seizing the opportunity for a little botany en route. There is one drawback; cycling and botany make difficult bedfellows. Riding along, I whizz past an interesting red flower. I turn the bike around for a second look, only to find I have been fooled yet again! It’s a sweet wrapper, commonly known as the Red Nestle Flower.

One small white/lilac flower growing along many of our main roads at this time of year, which is not so easily confused, is Danish Scurvy Grass (Cochlearia danica), flourishing as it does on the kerbstone, if not quite the gutter itself.

The English name, often well chosen and descriptive, is not in this case. Firstly, it is not a grass but a member of the cabbage family (Brassicaceae) and it is not Danish, but a native of these shores. It is however rich in vitamin C and was eaten by sailors to prevent scurvy.

Normally found by the coast, Danish Scurvy Grass packed its bags and started to move inland forty years ago. The reason? From the 1980s onwards we have been increasingly salting our roads during the winter months.

Most plants are not salt-lovers, but for Danish Scurvy Grass a salty habitat is a home from home. Moving inland along major A-roads at a rate of 10-15miles per year, the movement of traffic helps to spread the seeds further along the road network. Not unsurprisingly, its distribution map looks much like an AA road atlas of the British Isles.

Relatively few plants are salt-tolerant or halophytes, perhaps only 2%. Different plants have evolved different methods of growing in this hostile environment. Many will concentrate the salt in specialised cells known as salt glands, when filled to capacity these will rupture onto the exterior of the plant, giving many halophytes that blue-grey colour and salty covering. In some cases, as in Sea Pink or Thrift, the salt gland does not rupture but ultimately kills the leaf itself, with resultant leaf-drop and thus removal of the salt from the plant.

So on your next drive to the supermarket, for those much-needed provisions, cast your eyes kerbside and admire this interesting and recently arrived plant in Wharfedale.