Toxicity
Echium plantagineum contains pyrrolizidine alkaloids and is poisonous. When eaten in large quantities, it cause reduced livestock weight or even (in severe cases) death. Paterson's Curse can kill horses and irritate the udders of dairy cows and the skin of humans. After the 2003 Canberra bushfires over 40 recorded horses were put down after eating the weed.
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