Athertonia is a genus of tall trees, constituting part of the plant family Proteaceae. It is a monotypic taxon, and the sole described species is Athertonia diversifolia, commonly known as Atherton oak. It is a small to medium-sized tree and is endemic to restricted tablelands and mountainous regions of the wet tropics rain forests of north-eastern Queensland, Australia, where it is widespread. For example, it grows in the Atherton Tableland region with which it shares its name, from the colonial pastoralist John Atherton (1837–1913). Its closest relatives are Heliciopsis (South Asia) and Virotia (New Caledonia). A relative of the macadamia, it has potential as an ornamental tree and has an edible nut.
L.A.S.Johnson & B.G.Briggs
(C.T.White) L.A.S.Johnson & B.G.Briggs
Athertonia diversifolia was first described by Queensland Government Botanist C.T. White in 1918, who gave it the specific name derived from the Latin diversi- "different" and folium "leaves", from the fact that different-shaped leaves may be found on the one plant. He placed it in the genus Helicia. The Dutch botanist Hermann Sleumer placed it in the genus Hicksbeachia in 1955, where it stayed until Johnson and Briggs placed it in its own genus although conceded it was related to the former genus. Thus, it is the only member of the monotypic genus Athertonia. Common names include Atherton almond, Atherton Oak, White Oak, or cream silky oak.
Athertonia diversifolia grows as a tree 8 to 30 m (26 to 98 ft) tall. The trunk may be buttressed and reaches a diameter of 30 cm (12 in). Juvenile leaves are a simple oblong shape with finely toothed margins but are replaced by large lobed intermediate leaves which reach 60 cm (23.5 in) long. The adult leaves are variable in shape, lobed or entire, 12–20 cm (4.5–8 in) long and 5–9 cm (2–3.5 in) wide. Young branches and new growth are covered in fine rusty hair. Occurring from March to June, the flowers are cream and brown in colour and borne on 15–34 cm (6–13.5 in) long racemes. The lens-shaped fruit is 3.6–4.1 cm (1.4–1.6 in) long by 3.3–3.8 cm (1.3–1.5 in) wide and 1.9–2.6 cm (0.75–1.02 in) thick, dark blue, containing a woody-shelled nut with a large edible and crunchy kernel, which ripen in spring.
Distribution and habitatEdit
Athertonia diversifolia is found in north Queensland from Cape Tribulation south to Mt Bartle Frere. Its habitat is rainforest, generally from 700 to 1,150 metres (2,300 to 3,770 ft) in altitude. but is found at 400 m (1,300 ft) at Alexandra Creek. Much of its former habitat has been cleared. The soils are deep volcanic loams.
Atherton almond is cultivated to a limited extent for its edible nut, but makes a good specimen tree in large parks and has potential as an indoor foliage plant, or as a foliage plant in the cut flower industry. The species is readily propagated by seed.
Athertonia diversifolia is the floral emblem of the Atherton shire in north Queensland. It is known as the Atherton oak due to the shape of its immature leaves which resemble those of the English oak Quercus robur, to which it is unrelated.
- "Athertonia diversifolia (C.T.White) L.A.S.Johnson & B.G.Briggs". Australian Plant Name Index (APNI), IBIS database. Centre for Plant Biodiversity Research, Australian Government.
- Hyland, B. P. M.; Whiffin, T.; Zich, F. A.; et al. (December 2010). "Factsheet – Athertonia diversifolia". Australian Tropical Rainforest Plants. Edition 6.1, online version [RFK 6.1]. Cairns, Australia: Commonwealth Scientific and Industrial Research Organisation (CSIRO), through its Division of Plant Industry; the Centre for Australian National Biodiversity Research; the Australian Tropical Herbarium, James Cook University. Retrieved 18 April 2013.CS1 maint: extra punctuation (link)
- Weston, Peter H. (1995). "Athertonia" (online version). In McCarthy, Patrick (ed.). Flora of Australia: Volume 16: Eleagnaceae, Proteaceae 1. Flora of Australia series. CSIRO Publishing / Australian Biological Resources Study. 413–415, Figs 147, 178, Map 465. ISBN 978-0-643-05692-3.
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- Wrigley, John; Fagg, Murray (1991). Banksias, Waratahs and Grevilleas. Sydney: Angus & Robertson. pp. 76–77. ISBN 0-207-17277-3.
- Wet Tropics of Queensland. Australian Government.