Echium plantagineum, commonly known as purple viper's bugloss or Paterson's curse, is a species of Echium native to western and southern Europe (from southern England south to Iberia and east to the Crimea), northern Africa, and southwestern Asia. It has also been introduced to Australia, South Africa and the United States, where it is an invasive weed. Due to a high concentration of pyrrocilidine alkaloids, it is poisonous to grazing livestock, especially those with simple digestive systems, like horses. The toxins are cumulative in the liver, and death results from too much Paterson's curse in the diet.
Throughout these weeks their purple flowers bright in Menorca's prairies together with other herbs that bloom at the same time. Despite their beauty, people of the island do not have them in high esteem for being often the cause of death of horses that eat those plants when grazing.