There is a particularly common plant in Britain which, although beautiful to look at, is in fact, a poisonous, nasty piece of work. That plant is called Common Ragwort (Jacobaea vulgaris or Senecio jacobaea). Everyone knows Ragwort. It's bright-yellow flowers are a constant part of the British countryside during the Summer and is a favourite food plant for the caterpillar of the Cinnabar Moth (Tyria jacobaeae). It does however, contain several different poisonous alkaloids, enough to warrant a whole report by the World Health Organisation. Farm animals are usually not affected by Ragwort as they seem to know it and avoid it while it is growing in the fields. The problem comes when it is cut and dried and forms part of the hay, fed to cattle and horses. It can then start to attack the livers of the unfortunate animal, causing cirrhosis. But, what a beautiful plant it is, despite this 'dark side'.