Triodia pungens, a resinous spinifex grass, is proving to be a potential future bio-resource for the building industry and remote Aboriginal communities are likely to benefit from any new sustainable spinifex-harvesting industry. The Indjalandji-Dhidhanu people in the Camooweal region are an industrious Aboriginal community who would like to undertake spinifex harvesting, but questions such as when and how often should they harvest, and whether it would be sustainable in the long term, were critical to a successful spinifex industry. This thesis examines these questions through experiments, and a literature review of spinifex fire ecology and past Indigenous ecological knowledge of spinifex. It is argued that a lack of scientific studies in this region and an oversight by ethnographers to record how Aboriginal people selected spinifex plants for resin and fibre extraction both contribute to a lack of contemporary spinifex knowledge. The scientific literature however, argues that fire, heat and smoke are necessary to stimulate seed production and resprouting from plant crowns. As such, it was largely unknown how or whether spinifex would regrow after harvesting in the absence of heat and smoke. Gaps also appeared in the resin and fibre production, and flowering literature and it was unknown when spinifex produced resin and if flowering occurred annually in the region.
In an attempt to examine these questions, fire and harvesting experiments were conducted within a spinifex/snappy gum shrubland near Camooweal, north-west Queensland. The aim of this research was to develop an understanding of spinifex ecology and through this, develop knowledge of harvesting practices and spinifex resin-cycles and fibre production, which can underpin future commercial applications of sustainable spinifex-harvesting and Indigenous ecological knowledge revival in the study area.
This study monitored post-fire and post-harvest spinifex regeneration from 2009 to 2011. When Triodia pungens was intensively burned and harvested to ground level, spinifex hummocks were killed outright. Spinifex recovery is entirely by seedling regeneration and seedling numbers increase after the first wet season but taper off as mature hummock numbers increase in size. Ancillary harvesting tests found that partial removal of hummocks provides living plant tissue for spinifex to recover by rapid tiller production and subsequent stoloniferous regeneration. That is, many tillers (prop-roots) and stolons emerge from the host plant to form a new hummock within two wet seasons. Analyses of daily growth rates identified that removing sizeable portions of hummocks in the dry season provides the best results. This has important implications for spinifex regeneration where spinifex recovery is crucial to sustainable harvesting, and particularly for maximum spinifex resin and fibre production. This holistic strategic approach encourages the advancement of knowledge of spinifex and provides a vehicle for developing a successful spinifex industry run by Aboriginal people.