Rose Mallee (Eucalyptus rhodantha) is listed as Vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). It is also listed as Declared Rare Flora under the Western Australian Wildlife Conservation Act 1950.
The Rose Mallee is endemic to the Moora district in Western Australia. In 2006, there were 15 known populations of the species located between Watheroo and Three Springs. The four most northern populations were scattered over 11 kilometres west and south-west of Three Springs, while the 11 southern populations were distributed over several kilometres near Watheroo.
The Rose Mallee is a low spreading mallee growing up to 4m high, with smooth, greyish-brown bark and whitish-grey branches. The leaf is round to heart-shaped and usually pointed at the tip. The leaf size is 8cm long by 8cm wide, and it has a distinctive blue-grey colour. The leaves lack petioles (stalks) and are usually arranged in opposite pairs, often clasping the stems. The flower buds are grey, and the staminous flowers (flowers with a profusion of showy stamens) are large, growing up to 7.5 cm in breadth. The flowers are bright red although in some rare occasions they are found to be creamy yellow to white. They are borne on long thick peduncles up to 3.5cm long and are usually solitary but may have up to three flowers per inflorescence. The capsules (fruits) are woody, hemispherical to top-shaped, and grow up to 3cm long by 5.5cm wide with protruding valves. The dark brown seeds are winged. Flowering begins from July/September through until December/January.
The Rose Mallee grows on grey sandy to sandy loam soils, often with some gravel content, and over laterite in flat or slightly undulating country and hillslopes. The larger subpopulations occur in relatively undisturbed heath communities that are dominated by a range of shrubs including Ashby’s Banksia (Banksia ashbyi), One-sided Bottlebrush (Calothamnus quadrifidus), Prickly Poison (Gastrolobium spinosum), Two-leaf Hakea (Hakea trifurcata), Furrowed Hakea (Hakea sulcata), Flame Grevillea (Grevillea eriostachya) and various wattles (Acacia spp.). Most subpopulations are found in remnant bushland on private land, with some plants also occurring as scattered individuals in otherwise cleared and cropped paddocks and narrow degraded road reserves.
The main threats to the Rose Mallee are from past clearing of vegetation, mainly for agriculture; road, track and firebreak maintenance activities; uncontrolled fire; and competition from invasive weeds. Potential threats to the species are chemical spray drift from adjacent agricultural land, and increasing surface soil salinity; and altered fire regimes.
Information Source: Government of Australia, Department of Environment; and Department of Biodiversity, Conservation & Attractions, Western Australia