Allocasuarina robusta is a monoecious, rarely a dioecious shrub that typically grows to a height of 0.2–3 m (7.9 in – 9 ft 10.1 in) and has smooth bark.

[2][3][4] Mount Compass oak-bush was first formally described in 1927 by Ellen Dulcie Macklin who gave it the name Casuarina paludosa var.

[8] Allocasuarina robusta grows in heath and heathy woodland at higher elevations in an area of 184 km2 (71 sq mi) in the southern Mount Lofty Ranges, on the Fleurieu Peninsula to the south of Adelaide.

[2][3] Allocasuarina robusta is listed as "endangered" under the Australian Government Environment Protection and Biodiversity Conservation Act 1999.

[2] The main threats to the species include vegetation clearing, grazing pressure, road maintenance activities and weed invasion.