A Spectular Plant Gall
At this time of year plant galls (cecidia) are so numerous and varied that it is almost impossible to take a walk by a hedgerow and not notice at least a few varieties such as Oak Apples, Spangle Galls on Oak leaves, Bigbud on blackcurrants, red "Bean" galls on willow leaves and Witches' Brooms, like clusters of twigs, on Birch, to name but a few.Galls arise as a result of an attack by a parasite such as an insect, fungus, mite, nematode (eelworm) or bacteria to which the plant responds by producing an abnormal increase in the number of cells around the area of infection, or by the cells themselves becoming abnormally enlarged. The gall is produced wholly by the plant alone - the parasite plays no part in it apart from providing the stimulus.
The greener photograph above, shows what it is like when still growing on the path 'twixt Brookside surgery and the woods, by the stream. The red photograph left, shows a more developed plant along Carter's Hill Lane, off Mole Road. Click on either photograph to see a larger version.
Thanks to Alan Broodbank for this article and pictures.