the vampire plants lurking in the Sid Valley

Ed Dolphin, Sidmouth Arboretum (Image: Ed Dolphin)

Most plants make their own food using the sun’s energy, but there are plants that steal food by sucking the juices from other plants, some might call them vampire plants.

Our valley has at least five parasitic plants that hook into other species to take their sugar rich sap, two to top up their own manufactured food, but three have no leaves and rely totally on the efforts of neighbouring plants.

We all know about Mistletoe at Christmas, but it grows on trees not in the ground. It has green leaves that photosynthesise, but instead of roots it has organs called haustoria that grow into a host tree and extract the sap with its vital nutrients. There is a large bunch in the top of the Sycamore outside Culver House in Temple Street, and there is more in an Acacia beside Sidbury’s Millenium Meadow.

Yellow Rattle has its own green leaves, but it is also a parasite on the roots of larger grass species. People establishing wild flower meadows often use Yellow Rattle to weaken the grass and this stops it from swamping the more delicate wild flowers. Yellow Rattle does what it says on the tin, the flowers are yellow and the seed pods rattle when the seeds are ripe.

Yellow Rattle is just one of a whole family of parasitic plants, the Orobanchaceae. Many, such as the Broomrapes and Toothworts are total parasites which do not have leaves or chlorophyll and they look rather unearthly. There is a colony of the straw coloured Ivy Broomrape sucking the vital juices of the Ivy on the walls opposite the Apollonia Dentists in Elysian Fields. There are Purple Toothworts in a woodland garden in Broadway.

Perhaps the strangest parasite is Dodder, a tangle of thin red stems that throttles the Gorse on Muttersmoor. This is a cousin of Bindweed but has dispensed with the bother of growing leaves to feed itself, it puts all of the energy it drains from the unfortunate Gorse bush into producing flowers and seeds to maintain its hold on the harsh heathland environment.