Xanthorrhoea preissii (balga)
Xanthorrhoea preissii in Lesueur National Park, Western Australia
Xanthorrhoea preissii Endl.
balga (a Noongar Aboriginal name; grasstree is used for all members of the genus)
Coastal plains, near watercourses and inland forests, on a variety of substrates: grey to black sands, grey-brown loam, brown gravelly sandy clay, laterite and granite.
Hut construction, tool-making, igniting fires, source of edible beetle larvae, compass plant, medicinal uses, ornamental.
None known, although several other species of Xanthorrhoea are poisonous to cattle and it is thought likely that most species in the genus are poisonous.
About this species
Xanthorrhoea preissii was first described as new to science by the Austrian botanist Stephan Endlicher in the 1846 volume of Plantae Preissianae, but has been known to the Aboriginal people of Western Australia for millennia due to its many uses. Members of the genus Xanthorrhoea are commonly referred to as grasstrees, alluding to their tree-like appearance, with stout trunks and grass-like leaves fanning out from the crown. The dense flowering spikes of X. preissii can reach an impressive 3 m in length and are a prominent feature of the landscape in south-west Australia.
The plants are resistant to fire, which can stimulate prolific flowering, and the blackened trunks can re-sprout within a few months of a fire passing. Coloured bands caused by melting resin along the stems of grasstrees can be used to age plants and also to estimate the frequency of past fires affecting individual plants; this includes natural fires and those initiated by Noongar Aboriginal people as part of their land management. Some researchers have extrapolated the fire frequency data from individual balgas to whole landscapes in which they occur, and concluded that burning of the vegetation by Noongar Aboriginal people was frequent, leading to the initiation of inappropriate modern fire management to try to emulate past conditions. However, more recent research indicates that historical Noongar burns across landscapes were actually less frequent than supposed, and that the vegetation was allowed to recover for longer periods, even where individual balgas were burnt more frequently for cultural purposes.
Xanthorrhoea pecoris, Xanthorrhoea reflexa