In the early 1900s, prickly pear spread over 20 million hectares in Queensland, threatening ecosystems with its rapid growth of 1,000 hectares daily

By the early 1900s, prickly pear had spread across more than 24 million hectares in Queensland and New South Wales, expanding by about 400,000 hectares a year, according to Queensland Government historical records. At its height, the invasion was expanding by about 1 million acres, or 400,000 hectares, a year, roughly 1,000 hectares a day, according to Queensland Government historical accounts.

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