This essay narrates the ‘slow violence’, or creeping environmental harms taking place within contemporary environmental governance. It centres on a tall, dense and highly flammable introduced pasture species Gamba grass (Andropogon gayanus), which was listed as a weed across north Australian jurisdictions in 2008. Since this time, it has continued to expand its reach across the Northern Territory (NT). With a potential invasion range of over 380,000 sqkm2, this grass is a serious threat to many more-than-human worlds in the north, including Indigenous-led and Indigenous-owned environmental service economies and multimillion-dollar projects engaged in savanna fire management for carbon credits. Drawing upon fieldwork and interviews with a range of public servants, landholders and researchers in the NT between 2015 and 2018, this essay demonstrates how environmental governance is being undermined through specific institutions and practices. Through an ethnographic reading of weed management documents, including several legal permits to grow Gamba grass within the NT’s ‘eradication zone’, this essay narrates the diverse threads of a pressing ‘slow’ disaster. The unfolding story of Gamba grass, we suggest, is instructive for those seeking to understand the present and future of resource extraction or ‘extractivism’ in Australia and elsewhere.