Cyathea medullaris

Black fern (Korau)

Mamaku is the largest tree fern known. This fern is easily recognised by its black trunk with diamond pattern scars and the black "stalks." Maori ate baked pith as well as using it as poultice for sores or wounds. The gum has been used for worms and diarrhoea (according to Crowe). Young fronds are damaged by possums ( according to Parkinson)
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