B. australis may refer to: * Baptisia australis, the blue wild indigo or blue false indigo, a herbaceous perennial plant species native to North America * Barbosella australis, an orchid species * Brunonia australis, the blue pincushion or cornflower, a perennial herbaceous plant species found in Australia * Botryosphaeria australis, a synonym for Neofusicoccum australe, a fungus species