Soap mallee

Appearance

''Eucalyptus diversifolia'' is a mallee that typically grows to a height of 0.5–8 m and forms a lignotuber. It has smooth, mainly cream-coloured and grey bark. Young plants and coppice regrowth have sessile, egg-shaped to elliptic leaves arranged in opposite pairs, 40–75 mm long and 10–25 mm wide. Adult leaves are arranged alternately, the same olive-green or bluish-green on both sides, lance-shaped, 55–100 mm long and 10–22 mm wide on a petiole 12–18 mm long. The flower buds are arranged in groups of seven, nine or eleven in leaf axils on an unbranched peduncle 5–20 mm long, the individual buds on a pedicel 1–6 mm long. Mature buds are diamond-shaped, 5–12 mm long and 4–7 mm wide with a conical to beaked operculum. Flowering occurs between July and September or December to January and the flowers are white to cream-yellow flowers. The fruit is a woody, cup-shaped capsule 5–11 mm long and 8–11 mm wide, sessile or on a pedicel up to 7 mm long with the valves about level with the rim. The seeds are smooth glossy brown and pyramidal.

Distribution

Soap mallee grows in soils derived from limestone, often on exposed headlands. Subspecies ''diversifolia'' is found on the Eyre and lower Yorke Peninsulas, on Kangaroo Island in South Australia and eastwards to the Cape Nelson State Park with an isolated population near Aireys Inlet in Victoria, but it is absent from the Nullarbor Plain in far western South Australia. Subspecies ''hesperia'' occurs west of the Nullarbor Plain between Eucla, Caiguna, Cocklebiddy and Madura.

Uses

This species is able to produce large amounts of biomass, making 10 to 20 metric tons per hectare per year. In wheatbelt regions it is also beneficial as the tree will reduce salinity, give shade to stock, act as a windbreak and reduce erosion.