Lemon-Scented Gum, Lemon Scented Eucalyptus

Eucalyptus citriodora

Physical Characteristics

Eucalyptus citriodora is an evergreen Tree growing to 45 m (147ft 8in) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 10. It is in leaf all year, in flower from July to August. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry moist or wet soil and can tolerate drought.

Distribution

Australia - Queensland.

Habitats

Woodland Garden Sunny Edge; Dappled Shade; Bog Garden;

Edible Uses

Edible Parts: Manna Edible Uses: Produces a sweet manna-like substance that is scraped off the leaves and eaten[183].

Medicinal Uses

Antibacterial Astringent Eucalyptus leaves are a traditional Aboriginal herbal remedy. The essential oil found in the leaves is a powerful antiseptic and is used all over the world for relieving coughs and colds, sore throats and other infections[254]. The essential oil is a common ingredient in many over-the-counter cold remedies[254].An essential oil obtained from the leaves is antibacterial[152]. The essential oil obtained from various species of eucalyptus is a very powerful antiseptic, especially when it is old, because ozone is formed in it on exposure to air. It has a decided disinfectant action, destroying the lower forms of life[4]. The oil can be used externally, applied to cuts, skin infections etc, it can also be inhaled for treating blocked nasal passages, it can be gargled for sore throat and can also be taken internally for a wide range of complaints[4]. Some caution is advised, however, because like all essential oils, it can have a deleterious effect on the body in larger doses[4]. An oleo- resin is exuded from the tree[238]. It can also be obtained from the tree by making incisions in the trunk[4, 152]. This resin contains tannin and is powerfully astringent, it is used internally in the treatment of diarrhoea and bladder inflammation[4, 152, 238], externally it is applied to cuts etc[4, 152].

Known Hazards

Citronellal, an essential oil found in most Eucalyptus species is reported to be mutagenic when used in isolation[269]. In large doses, oil of eucalyptus, like so many essential oils has caused fatalities from intestinal irritation[269]. Death is reported from ingestion of 4 - 24 ml of essential oils, but recoveries are also reported for the same amount[269]. Symptoms include gastroenteric burning and irritation, nausea, vomiting, diarrhoea, oxygen deficiency, ,weakness, dizziness, stupor, difficult respiration, delirium, paralysis, convulsions, and death, usually due to respiratory failure[269].