A flora survey of the Stony Head Training Area, northern Tasmania, was conducted in 2020–2021 as a collaboration between the Tasmanian Museum and Art Gallery’s Expeditions of Discovery and the Australian Biological Resources Study Bush Blitz programs. With a long historical use as an artillery range, the 5000-ha area contains a range of geologies, has a low profile with average elevations under 100 m asl, and its vegetation consists largely of heathy woodlands and coastal heathlands. It contains a range of relatively undisturbed, high-quality native habitats and populations of several threatened species. The survey targeted vascular plants, bryophytes and lichens, and recorded a total of 575 taxa. Nine lichens are new records for Tasmania — Buellia hypostictella, Caloplaca gilfillaniorum, Cladonia subradiata, Graphis geraensis, Lecanora intumescens and Opegrapha diaphoriza — all previously also known from mainland Australia, and Micarea rhabdogena, M. xanthonica and Pseudothelomma ocellatum, which represent first records for the Southern Hemisphere. Biogeographical and ecological patterns in the flora, the contribution of vegetation remnants to flora conservation, and the ongoing importance of surveys and alpha-taxonomy for documenting biodiversity are discussed. Our findings are consistent with a body of research showing a trend of healthy populations of threatened taxa within military training areas. Keywords: Tasmania, biodiversity, lichens, species discovery, threatened species, vegetation remnants, fire, habitat loss, conservation.