About Eucalyptus polyanthemos Schauer
Eucalyptus polyanthemos Schauer is a tree that typically grows to 20 metres (66 feet) tall and does not form a lignotuber. It has fibrous or flaky bark on its trunk and larger branches, with smooth, mottled greyish, cream-coloured, and yellow bark on upper sections; occasionally it has smooth bark across the entire tree. It often has a crooked trunk and is well known for its domed canopy of greyish foliage.
Leaves on young plants are green to bluish grey, broadly egg-shaped to roughly round, 25–80 mm (0.98–3.15 in) long, 25–65 mm (0.98–2.56 in) wide, and borne on a petiole. Mature crown leaves are the same dull green, bluish, or greyish shade on both sides, with shapes ranging from lance-shaped to egg-shaped or round. They are 50–110 mm (2.0–4.3 in) long, 18–50 mm (0.71–1.97 in) wide, tapering to a petiole that is 10–27 mm (0.39–1.06 in) long. Leaf veins are distinct, and the marginal vein is notably far from the leaf edge.
Flower buds are arranged in groups of seven on the ends of branchlets, on a branching peduncle 2–10 mm (0.079–0.394 in) long, with individual buds borne on pedicels 1–5 mm (0.039–0.197 in) long. Mature buds are oval to diamond-shaped, 3–5 mm (0.12–0.20 in) long and 2–3 mm (0.079–0.118 in) wide, with a conical to slightly beaked operculum. Flowering occurs in October and November (spring in Australia), and the flowers are white. The fruit is a woody barrel-shaped to conical capsule, 3–6 mm (0.12–0.24 in) long and wide, with valves that sit below the level of the capsule rim.
In distribution and habitat, subspecies longior grows in taller forest in the foothills of far eastern Victoria. Subspecies marginalis is also found in Victoria, occurring between Greater Bendigo National Park and Stawell, with outlying populations near Bacchus Marsh; it grows in forest or woodland on dry, gravelly soils. Subspecies polyanthemos is widespread on the slopes and tablelands of central and southern New South Wales. Subspecies vestita is found in both Victoria and New South Wales. It grows in woodland south of Gulgong, with a small outlying population in the upper Hunter Valley, and is widespread in Victoria east of Ararat, growing on poor stony soils, usually on ridges and slopes.
In ecology, the larvae of the moth Trichiocercus sparshalli and the eucalyptus leaf mining sawfly Phylacteophaga froggatti feed on the leaves of this tree. Large, old trees may form hollows that are used as nesting sites for owls, including the barking owl (Ninox connivens). This species has been recorded as an invasive species in California, where it is an introduced plant also known by the common names silver dollar gum, redbox, and redbox gum.
In horticulture, Eucalyptus polyanthemos is noted for its drought tolerance. While it is usually considered slow growing, the growth rate of newly planted trees can be boosted by growing in improved soil with good drainage, plus irrigation during the first two years after planting. The species is moderately resistant to Armillaria root rot, and requires a minimum cultivation temperature of −10 °C (15 °F). In floristry, its juvenile foliage is used in floral arrangements.
