Litchfield, NT

Natural populations

Alphitonia excelsa is widely distributed from the Kimberley region of Western Australia, across the Top End and Gulf region of Northern Territory, across the medium to high rainfall areas of Queensland, extending south to southern coastal regions of New South Wales [1]. This species is often associated with mesic sites such as closed forests. It ranges from a large shrub on adverse sites to a tall tree up to 35 m tall on more favourable sites and occurs across a wide range of habitats and soil types [1].

Flowering and seeds

This species has a wide latitudinal gradient in flowering times with flowering commencing earliest in northern populations (flowering November to March with fruits ripening June to September) and later in southernmost populations (flowering April to May with fruits ripening October to January) [1]. There are about 8 viable seeds per gram [2]. Nicking or boiling the seeds in water for a minute at 100°C is required to encourage germination. The seeds start to germinate in about 4 days if grown at 25-30°C [2]. Cuttings strike readily [3].

Cultivation and uses

Alphitonia excelsa can be grown on wide range of well-drained soils and has considerable ornamental value. Its wood is suitable for cabinet work, plywood, flooring, parquetry and panelling [1].

Key descriptors:
Climate parameters
Mean annual rainfall: 650-1250 mm
Rainfall distribution pattern: summer or uniform
Mean annual temperature: 17-28 °C
Mean max. temperature of the hottest month: 29-38 °C
Mean min. temperature of the coldest month: 3-8 °C
Frosts (approx. no. per year): frost free or more or less frost free or up to 20
Frost intensity: light to moderate (0 to -5°C)
Altitude: 0-1050 metres
Tolerance of climate extremes
Drought: known to be moderately drought tolerant or known to be tolerant of protracted droughts
Frost: tolerates frosts in the 0° to -5°C range
Wind: tolerates salt-laden coastal winds
Soil factors
Texture: clay loam, duplex texture contrast soils, light to medium clay (35-50% clay) or sand
Soil pH reaction: acidic (less than 6.5) or neutral (6.5-7.5)
Soil depth: moderate to deep (30-100 cm or greater)
Drainage:  well-drained
Salinity: non-saline
Tolerance of adverse soils
Extremes in pH: acidity
Extremes in texture: clayey or sand
Salinity: nil - sensitive to saline soils
Soil waterlogging tolerance: nil - sensitive to waterlogged soils
Biological traits under cultivation
Habit: deciduous in colder areas but usually evergreen, tree 10-20 m tall or tree > 20 m tall
Longevity: short-lived less than 15 years
Growth rate: fast
Root system: moderate to deep
Erosion control potential: excellent for clayey sites or excellent for sandy sites
Windbreak potential: tolerates salty coastal winds
Shade tolerance: grows best in full sunlight
Wood density: low (less than 600 kg/cubic metre)
Carbon sequestration potential: low or moderate
Potential farm use: good ornamental attributes
Specialty products: high tannin content in bark
Traditional Aboriginal uses: fish poison, medicinal
Urban use: good as an ornamental or amenity plant or suitable as a screen or hedge
Wood products: craftwood (for turnery etc.), flooring (including parquetry), light construction, panelling, speciality timber for quality furniture, wood composites
Potentially undesirable attributes
Susceptibility to disease or predation: foliage highly susceptible to insect predation or pathogenic leaf diseases
Foliage: low to moderate susceptibility to browsing
Weediness: high potential based on its biology


[1] Doran JC, Turnbull JW (eds.) (1997) Australian Trees and Shrubs: species for land rehabilitation and farm planting in the tropics. Australian Centre for International Agricultural Research, Canberra [ACIAR books online: Accessed 24/02/2008]

[2] Gunn BV (2001) Australian Tree Seed Centre Operations Manual. Internal Publication, CSIRO Australian Tree Seed Centre, ACT.  [Online at Accessed March 2008]

[3] Floyd AG (1989) Rainforest Trees of Mainland South-eastern Australia. Inkata Press.

Internet links

Australian National Botanic Gardens website: