Species are known by the name grass tree. Mycorrhiza is fungi that live in a mutually beneficial relationship with the grass tree roots. The trunk of this grass tree is underground. "Taplan" is an aboriginal word meaning "grass tree". Brushwood, grass tree needles and dry rushes were commonly used for thatching. The common name is the bottlebrush grass tree. Xanthorrhoea semiplana is a species of grass tree found in south-eastern Australia. Richea pandanifolia, the pandani or giant grass tree, is a distinctive endemic Tasmanian angiosperm. The grass tree also suffers from a condition known as phytophthera dieback. The perennial grass tree is found in the south east of South Australia. The grass tree has a symbiosis relationship with Mycorrhiza deep in its root system.