Eucalyptus polybractea
| Eucalyptus polybractea | |
| Light: |  |
| Moisture: |    |
| Soil pH: | 5.6-8.4 |
| Evergreen | |
| Height: | 20' |
| Speed: | Fast |
| Open Woods Forest | |
| Native to: | |
| Edible Rating: |  |
| Medicinal Rating: |  |
| Tea: | Yes |
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Eucalyptus polybractea (common name: blue mallee)
Propagation: Seed - surface sow February/March in a sunny position in a greenhouse[1][2][3]. Species that come from high altitudes appreciate 6 - 8 weeks cold stratification at 2°c[4]. Pot up the seedlings into individual pots as soon as the second set of seed leaves has developed, if left longer than this they might not move well. Plant out into their permanent positions in early summer and give them some protection from the cold in their first winter. The seed can also be sown in June, the young trees being planted in their final positions in late spring of the following year. The seed has a long viability[4].
Cultivation: Prefers a sunny position in a moderately fertile well-drained moisture retentive circum-neutral soil[4]. Tolerates poor and dry soils, especially those low in mineral elements[4]. Established plants are drought tolerant[4].
This species is cultivated in Australia for its essential oils[5]. It is of very doubtful hardiness in Britain, though it might succeed outdoors in the mildest areas of the country[4].
Eucalyptus species have not adopted a deciduous habit and continue to grow until it is too cold for them to do so. This makes them more susceptible to damage from sudden cold snaps. If temperature fluctuations are more gradual, as in a woodland for example, the plants have the opportunity to stop growing and become dormant, thus making them more cold resistant. A deep mulch around the roots to prevent the soil from freezing also helps the trees to survive cold conditions[4]. The members of this genus are remarkably adaptable however, there can be a dramatic increase in the hardiness of subsequent generations from the seed of survivors growing in temperate zones[4].
Eucalyptus monocultures are an environmental disaster, they are voracious, allelopathic and encourage the worst possible attitudes to land use and conservation[4].
Plants are shallow-rooting and, especially in windy areas, should be planted out into their permanent positions when small to ensure that they do not suffer from wind-rock[6]. They strongly resent root disturbance and should be container grown before planting out into their permanent position[1].
Plants respond well to coppicing[7].
The flowers are rich in nectar and are a good bee crop[4].
Range: Australia - New South Wales, Victoria.
Habitat: Poor clayey and sandy soils in the semi-arid interior[8]
Edibility: An essential oil from the leaves is used as a food flavouring in baked goods, ice cream and sweets[9].
Medicinal: 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[10]. The essential oil is a common ingredient in many over-the-counter cold remedies[10].
The essential oil obtained from the leaves is antirheumatic, antiseptic and expectorant[5][8][7]. This is one of the main species used for its medicinal oils, which contain up to 85% eucalyptol[5]. 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[5]. 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[5]. Some caution is advised, however, because like all essential oils, it can have a deleterious effect on the body in larger doses[5].
Usage: The leaves yield up to 1.3% of an essential oil. It is used medicinally and as a food flavouring[8][7].
The wood is used as a fuel[7].
Pollinators: Bees
Soil: Can grow in light, medium, and heavy soils.
Drainage: Prefers well drained soil.
In Leaf: Evergreen
Flower Type: Hermaphrodite
Known Hazards: Citronellal, an essential oil found in most Eucalyptus species is reported to be mutagenic when used in isolation[11].
In large doses, oil of eucalyptus, like so many essential oils has caused fatalities from intestinal irritation[11]. Death is reporte
Links
References
- ↑ 1.0 1.1 Bean, William. Trees and Shrubs Hardy in Great Britain. Murray, 1981.
- ↑ Sheat, Wilfrid. Propagation of Trees, Shrubs and Conifers. St Martin, 1948.
- ↑ Rice, Graham. Growing from Seed Volume 2. Thompson and Morgan, 1988.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 Grieve, Margaret. A Modern Herbal. Penguin, 1984.
- ↑ Genders, Roy. Scented Flora of the World. Robert Hale, 1994.
- ↑ 7.0 7.1 7.2 7.3 Ewart, Alfred. Recording Census of the Victorian Flora. 1923.
- ↑ 8.0 8.1 8.2 Lassak, Erich and Tara McCarthy. Australian Medicinal Plants.
- ↑ Facciola, Stephen. Cornucopia - A Source Book of Edible Plants. Kampong Publications, 1990.
- ↑ 10.0 10.1 Chevallier, Andrew. The Encyclopedia of Medicinal Plants. Dorling Kindersley, 1996.
- ↑ 11.0 11.1 Duke, James. Handbook of Energy Crops. 1983.