About

Pteridium esculentum, commonly known as bracken fern, austral bracken or simply bracken, is a species of the bracken genus native to a number of countries in the Southern Hemisphere. Although it is now known to contain the carcinogen ptaquiloside, the rhizome of the plant was a staple in traditional Māori diets in New Zealand and was eaten by Indigenous Australians.

Safety

Pteridium esculentum contains the known bracken carcinogen ptaquiloside. Concentrations of ptaquiloside in bracken in New Zealand vary greatly, and in a high proportion of stands ptaquiloside is not found. A higher incidence of ptaquiloside, and some very high concentrations, are found in areas where bovine enzootic haematuria and/or acute haemorrhagic syndrome was known to occur. Traditional Māori cooking techniques may have lessened the content of ptaquiloside.

Pteridium esculentum contains silica structures, which over time can grind down teeth, something seen in many Māori archaeological sites. The plant is also known to cause constipation.

Where it grows

It is found in all states of Australia apart from the Northern Territory, as well as New Zealand, Norfolk Island, Malaysia, Polynesia, and New Caledonia. Within Victoria it is widespread and common to altitudes of 1,000 m (3,300 ft). In New South Wales, it occurs across central, eastern and southern parts of the state. It can also be weedy and invade disturbed areas. In Western Australia, it grows near the southern and western coastlines, as far north as Geraldton. In Queensland, it is found in many locations.

Other Pteridium plants

Hairy brackenfern · Bracken · Bracken