Scientific Name : Eucalyptus tereticornis Sm.
Common Name : Forest Gray Gum, Forest Red Gum
Chinese Name : 細葉桉
Family : MYRTACEAE
Local distribution status : Exotic species
| Origin | Native to New Guinea and Australia, including New South Wales, Queensland and Victoria. |
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| Meanings of name | The specific epithet tereticornis refers to its long and horn-like calyptra. |
| Ecology | The leaves of Eucalyptus spp. (e.g., E. tereticornis, E. robusta, E. camaldulensis) serves as the primary food source for koalas. The essential oils from the leaves are pernicious to most animals, however, show no effect on koalas whose digestive tract has armed the microorganisms that can degrade the toxin and intake the nutrients from the leaves. For the sake of obtaining this marvellous ability, rather than inheriting strictly from genetic materials, a baby koala can gain the microorganisms from its mother faeces; a primitive but easy way, eat it! |
| Vitality | Forest Gray Gum is resilient to diverse environments such as dry climates and light frosts. A good planting prefers slightly sticky and fertile soils. |
| Application | The essential oils derived are usually processed into fragrance, larvicidal oil and medicinal oil. The wood is durable, fine, dense, with interlocked grain; therefore, it is always used for making fuel wood, paving and windmill bearings. Forest Gray Gum is a fast-growth tree and constitutes one of the predominant eucalyptus in afforestation work. In Hong Kong, there is a large plantation with Forest Gray Gum in Nam Sang Wai. |
| Growing habit | Evergreen tree. |
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| Height | To 25 m. |
| Stem | Bark greyish white to brown, smooth, exfoliating in irregular flakes or long strips, persistent at trunk base, coarse, black. Branchlets slender, drooping. |
| Leaves | Simple leaves alternate. Blade of juvenile tree ovate to broadly lanceolate. Blade of adult tree glabrous, narrowly lanceolate, slightly twist at maturity, both surfaces bright green, glabrous, concolourous. |
| Flower | Flowers always 5-8 clustered in an umbel inflorescence, axillary. Flowers buds long ovoid, calyptra conical to long conical, hypanthium hemispheric. Stamens many, white, protruded. |
| Fruit | Capsules subglobose to ovoid, floral disk raised, with prominent rim, valves 4-5, strongly exserted. From green to dark brown when mature. |
| Flowering period | June to August in Hong Kong. |
| Fruiting period | August to September in Hong Kong. |
Scientific name above is based on Hong Kong Herbarium website :
https://herbarium.gov.hk/en/hk-plant-database/plant-detail/index.html?pType=species&oID=6919
Scientific names from other databases :
― Flora of China : Eucalyptus tereticornis Smith
― Plant of the World Online : Eucalyptus tereticornis Sm.