Scientific Name : Corymbia torelliana (F. Muell.) K. D. Hill & L. A. S. Johnson
Common Name : Cadaga
Chinese Name : 毛葉桉
Family : MYRTACEAE
Local distribution status : Exotic species
| Origin | Queensland. |
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| Meanings of names | The generic name Corymbia refers to its blossoms clustered in an umbel. The specific epithet torelliana was named after Count Luigi Torelli (1810-1877), a member of the Italian senate who proposed the application of eucalyptus for drying the Pontine Marshes for the sake of minimizing the risk of malaria. |
| Ecology | The seeds of Cadaga are primary driven by gravity and bees. When the fruit is mature, it pops and most of the seeds fly out from the valves and drop on the ground nearby. Although gravity is an energy-saving dispersal method, it crams the descendants into a certain area and intensifies the intraspecific competition. Under the selective pressure, Cadaga has engaged in a mutualistic interaction with bees. The tree secretes sticky resin droplets at the edge of every valve, for the sake of clinging the seeds away from the gravitational force. The resins are attractive to bees which use for building nests. The seeds calmly attach to and are dispersed miles by the bees during the flight back to their nests. The long dispersal is thought to increase the survival rate for higher probability to germinate in a better-off environment. |
| Vitality | Cadaga is fast-growing and highly tolerant to drought, heat, cold, wind and barren soils. |
| Application | The leaves can treat sore throat and unpleasant breathing triggered by bacterial infection; the leaf extracts can treat lung disease. The towering height and robust trunk render the tree excellent windfirm and thus has been exploited for windbreaks in many countries such as Florida of the United States. |
| Growing habit | Large evergreen tree. |
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| Height | To 30 m. |
| Stem | Bark greyish green to white, exfoliating but persistent at trunk base, coarse, dark brown. Branchlets terete, densely hirsute when young, glabrous after lignification. |
| Leaves | Leaf blade alternate, ovate, base rounded, apex acute to acuminate.Leaf margin entire, abaxial leaf pubescent, petiole densely tomentose. Young leaves and petioles densely red tomentose. |
| Flower | Inflorescences paniculate, terminal or axillary, each umbel always 3-7 flowered. Hypanthium semiglobose, calyptra green, rounded or conical to slightly beaked. Stamens many, white. |
| Fruit | Capsules globose, urn-shaped, disc descending, valves 3. |
| Flowering period | October to November in Hong Kong. |
| Fruiting period | / |
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=6922
Scientific names from other databases:
― Plant of the World Online: Corymbia torelliana (F.Muell.) K.D.Hill & L.A.S.Johnson
― Flora of China: Eucalyptus torelliana F. Mueller.