Cerbera inflata, commonly known as the cassowary plum, grey milkwood, Joojooga, or rubber tree, is a plant in the family Apocynaceae endemic to northeast Queensland, specifically the Atherton Tablelands and adjacent areas.
Description
The cassowary plum is a tree up to 30 m (98 ft) in height with a grey fissured trunk. Leaves are glabrous (smooth), lanceolate, dull green above and paler below, and crowded towards the end of the twigs. They measure from 10 to 26 cm (3.9 to 10.2 in) long and 1.5 to 3 cm (0.6 to 1.2 in) wide with 33 to 37 lateral veins. All parts of the tree produces a copious milky sap when cut.[4][5][6]
The inflorescence is a much branched cyme up to 15 cm (6 in) with usually more than 50 flowers. The flowers have 5 white sepals, a long corolla tube about 16 mm (0.6 in) in length by 2 mm (0.08 in) wide with 5 free lobes at the end. They are white with a cream or green centre, about 10 to 15 mm (0.4 to 0.6 in) in diameter, and have a sweet scent.[4][5][6]
Fruits are a bright blue-purple drupe measuring about 7 cm (2.8 in) long by 3 cm (1.2 in) wide, slightly pointed and the end away from the pedicel (stem), with a single large seed.[4][5][6]
There is potential confusion regarding the taxon C. dilatata. To clarify, C. dilatata Markgr. was first described in 1927, but has since been determined to be a synonym of C. odollam Gaertn.[8] The subject of this article was originally described as C. dilatata S.T.Blake but was renamed in 1959 due to the earlier usage of that combination.[5] Of these three taxa, only C. odollamGaertn. and C. inflataS.T.Blake are now considered legitimate. However, there are still many references and sightings labelled with C. dilatata, and any that occur outside Australia are likely to be C. odollam.
Distribution and habitat
Cerbera inflata is endemic to Queensland. It grows in well developed rainforest in the foothills and uplands from Innisfail to the Atherton Tableland. The altitudinal range is from 100 to 800 m (330 to 2,620 ft).[4][6]
Ecology
Cassowaries eat the fallen fruit whole, and are the major dispersal agent for the species.[6]