Salvation Jane

This is Echium plantagineum, better known (depending on where in Australia you come from) as either Salvation Jane or Paterson's Curse, and it originally hails from the Mediterranean region. The seeds were first brought to Australia from Europe in the 1880s, to be added to the garden of Jane Paterson, who lived near Albury.  From there it started spreading, and it is now a common weed in New South Wales, Victoria, Tasmania, the Australian Capital Territory, parts of South Australia, southern Queensland and south western Western Australia. And it's still spreading.

It's very pretty, with masses of purplish-blue flowers forming carpets across entire paddocks after rain. But it can also be deadly. Horses and pigs are particularly vulnerable to the toxic effects it has on the liver. Cattle and sheep are more resistant, and in fact it has carried stock through bad periods of drought in South Australia (and that's where the name Salvation Jane is most widely used), but too much of it in their diet can make even these animals very sick.