Timor White Gum, Timor Mountain Gum, Half-barked Tree

Scientific Name : Eucalyptus urophylla S. T. Blake
Common Name : Timor White Gum, Timor Mountain Gum, Half-barked Tree
Chinese Name : 尾葉桉
Family : MYRTACEAE
Local distribution status : Exotic species

Anecdotes on plants

Origins Southeast Indonesian islands and Timor-Leste.
Meanings of name The Chinese name “Tail-leafed Eucalypt (尾葉桉)” vividly illustrates the shape of its leaves, as the tip of the leaf extends into a “tail”. This Chinese name is derived from its scientific name, which the species epithet “urophylla” combines by the words “uro (tailed)” and “phyllus (leaved)”.
Since the species grows on the mountains of Timor island, with trunk in colour of greyish white, it has also gained the English names “Timor White Gum” and “Timor Mountain Gum”. In Australia, this species is called the “Half-barked Tree”, which interestingly describes the characteristics of its bark which is peeling off yet partially attached to the main trunk.
Applications The Timor White Gum is widely cultivated as plantations in tropical regions, including Brazil, Vietnam, China and Australia. The Timor White Gum is also an important economic crop, with its wood often turned into pulps and papers. Timber from old trees can be used for general construction, while younger trees provide good source of firewood and charcoal, and can be further processed into other wooden products such as boards, cabinets and plywood.
Ecology The Timor White Gum is native to the montane forests generically composed of volcanic rocks. It grows in a wide range of altitudes, from the sea level to 3000 meters above sea level. It prefers a hot, humid and rainy environment. The species exhibit high adaptability, fast growth rate and ability to grow well in degraded and barren soil. It is noteworthy that Timor White Gum and other Eucalyptus species shows a certain degree of allelopathy, which inhibits the growth of other native plants. Planting Eucalyptus in large scales will sabotage the local habitats and disadvantage the biodiversity of ecosystem.

Traits for identification

Growing habit Evergreen tree.
Height To 50 m.
Stems Bark of upper trunk greyish white to light brown, smooth. Lower trunk persistent with decorticated strips in colour of reddish brown, rough.
Diameter at Breast Height (DBH) of main trunk to 2 m. Height of trunk reach two third of the whole tree.
Leaves Mature leaves broadly lanceolate, slightly falcate. Apex caudate acuminate, base cuneate, sometimes oblique, margin slightly thickened and recurved, texture leathery.
Dark green and shining adaxially, pale green and duller abaxially, densely punctate on both surfaces. Petiole grooved above.
Flowers Inflorescence axillary, with 5 to 8 flowers. Structure of flower specialised. Hypanthium cyathiform (cup-shaped). Sepals and petals fused to form a conical calyptra (a cap-like covering), apex apiculate. Hypanthium and calyptra form a waterdrop-shaped flower bud. Calyptra detach upon anthesis. Stamens many, white.
Fruits Cyathiform (cup-shaped) to obconical. Valves 3 to 5, present internally, partly exserted.
Flowering period September to November in Hong Kong.
Fruiting period May to June in Hong Kong.
Remarks

Scientific name above is based on Hong Kong Herbarium website : https://www.herbarium.gov.hk/en/hk-plant-database/plant-detail/index.html?pType=species&oID=11087

Scientific names from other databases
Plants of the World Online : Eucalyptus urophylla S.T.Blake

Reference