Eucalyptus dalrympleana

Eucalyptus dalrympleana is a tree that typically grows to a height of 40 m (130 ft) and forms a lignotuber. It has smooth white to yellowish bark, sometimes with a short stocking of rough bark. Young plants and coppice regrowth have leaves arranged in opposite pairs and are egg-shaped or heart-shaped to more or less round, 25–70 mm (0.98–2.76 in) long and wide. Adult leaves are arranged alternately, lance-shaped to curved, the same colour on both sides, 80–220 mm (3.1–8.7 in) long and 10–40 mm (0.39–1.57 in) wide on a petiole 12–35 mm (0.47–1.38 in) long. The flower buds are arranged in groups of three or seven in leaf axils on a peduncle 3–12 mm (0.12–0.47 in) long, the individual buds sessile or on a pedicel up to 3 mm (0.12 in) long. Mature buds are oval, green to yellow, 6–10 mm (0.24–0.39 in) long and 3–6 mm (0.12–0.24 in) wide with a conical to rounded operculum. Flowering mainly occurs between March and June and the flowers are white. The fruit is a woody cup-shaped, bell-shaped or hemispherical capsule 3–8 mm (0.12–0.31 in) long and 5–9 mm (0.20–0.35 in) wide.[2][3][4][5]

Eucalyptus dalrympleana was first formally described in 1920 by Joseph Maiden from a specimen collected by Wilfred de Beuzeville near Yarrangobilly. The description was published in Maiden's book, The Forest Flora of New South Wales.[6][7] The specific epithet (dalrympleana) honours the forester, Richard Dalrymple Hay.[2]

In 1962, Lawrie Johnson described two subspecies and the names have been accepted by the Australian Plant Census:

• Eucalyptus dalrympleana Maiden subsp. dalrympleana[8] has flower buds arranged in groups of three;[4]
• Eucalyptus dalrympleana subsp. heptantha L.A.S.Johnson[9] has flower buds and flowers in groups of seven.[4]

Mountain gum grows in woodland and forest at higher elevations in far south-eastern Queensland, New South Wales, Victoria, South Australia and Tasmania. Subspecies heptantha is only found in far south-eastern Queensland and on the northern tablelands of New South Wales. Subspecies dalrympleana occurs south from the central and southern tablelands of New South Wales.[3][4] The species is rare in South Australia where it only occurs in the Mount Lofty Ranges.[10]

In cultivation in the UK, E. dalrympleana is fully hardy down to −15 °C (5 °F) but prefers some shelter. It grows best in full sun. It has gained the Royal Horticultural Society's Award of Garden Merit.[11][12]

• Holliday, I. A field guide to Australian trees (3rd edition), Reed New Holland, 2002

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