Common Name: Tallow Wood

General Information

Eucalyptus microcorys is an evergreen tree; it usually grows from 30 - 60 metres tall. The straight bole can be up to 65% the total height of the tree and up to 210cm in diameter[, , ].
The tree has been harvested from the wild for local use as a source of wood, tannins and essential oil. It has been planted for timber in DR Congo, Rwanda, Ethiopia, Kenya, Uganda, Tanzania, Malawi, Zambia, Angola, Zimbabwe, Madagascar and South Africa[].

Known Hazards

None known

Botanical References

,

Range

Australia - northeast New South Wales, southeast Queensland

Habitat

Forests, usually in hilly or mountainous country. Part of this range experiences snow and frost in the winter[]. Trees occasionally form the over-storey in rainforests.

Properties

Other Uses Rating
Habit	Evergreen Tree
Height	45.00 m
Growth Rate	Fast
Pollinators	Bees, Insects
Cultivation Status	Cultivated, Wild

Cultivation Details

Eucalyptus microcorys is a species of the subtropical zone of eastern Australia, where it is found at elevations up to 800 metres. Summers are hot and moist, winters can be dry, with a dry season of around 3 months. Mean annual rainfall is within the range 900 - 1,500mm; mean maximum temperature of the hottest month is 32°c; mean minimum temperature of the coldest month is 5°c, and there are generally around 10 - 30 frosts a year[]. When dormant, the plant can survive temperatures down to about -5°c, but young growth is more tender and can be severely damaged at 0°c[].
Prefers a sunny position in a moderately fertile well-drained moisture retentive circum-neutral soil[]. Tolerates poor and dry soils, especially those low in mineral elements[]. Prefers a pH in the range 5.5 - 7, tolerating 5 - 8[]. Established plants are drought tolerant[].
The plant develops a lignotuber - this is a woody tuber that starts to develop near the base of seedlings and can become massive in the mature plants of some species. It possesses embedded vegetative buds, allowing the plant to regenerate following crown destruction, for example by fire[].
When grown in plantations the tree grows slowly at first but later makes a very dense dark forest[].
Whilst most Eucalyptus species, grown in small numbers outside their native range, can be an attractive and useful addition to the landscape, certain species (including this one) are more problematic. When grown in monocultures, especially outside their native range, they can become an environmental disaster. They are voracious, especially in their use of water; they are allelopathic, inhibiting the growth of the native flora; they reduce habitats for native fauna; and encourage the worst possible attitudes to land use and conservation[].
Annual wood production potential is 8 - 30 cubic metres per hectare[].
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[]. Many members of this genus are remarkably adaptable however, and there can be a dramatic increase in the hardiness of subsequent generations from the seed of survivors growing in temperate zones[].
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[]. They strongly resent root disturbance and should be container grown before planting out into their permanent position[].

Edible Uses

None known

Medicinal

Kino resin, obtained from the trunk, is very astringent. Diluted, it can be taken internally as an effective treatment for dysentery, working because it is not absorbed at all from the stomach and only very slowly from the intestine, and is thus able to directly treat the lower part of the intestine. It can be used as a gargle and mouthwash to treat relaxed throat, loose teeth[, ].
Applied externally as a wash, it is an effective styptic and can used to treat cuts and skin problems[].

Agroforestry Uses:

The tree is used in windbreaks and as a shade tree[].
The flowers are rich in nectar and are a good bee forage[, ].

Other Uses

The fresh leaves of this tree yield 1.96% of an essential oil of an acid reaction, and a specific gravity of .896. This oil
does not have a very agreeable odour, but it probably might be found useful in varnish-making. The oil distilled from the young leaves is of finer quality and more fragrant than that from the mature foliage[].
An essential oil is obtained from the leaves. Total quantity of the oil, and its composition, can vary widely from plant to plant, but we have reports that the fresh leaves contain around 0.7 - 0.8% essential oil. The main components include 1,8-cineole (24 - 57%), pinene (12 - 27%))[].

The bark contains tannins[].
A small quantity of kino resin is obtained from the trunk. Kino resins are rich in tannins and are very astringent. Soluble in water, they can be used medicinally; in tanning; as well as for preserving and dyeing natural fibres. When boiled in an iron pot they produce a thick, dark liquid that can be used as an ink[].
The resin oozes naturally from wounds in the trunk and can be tapped by making incisions in the bark. At first it is a thick liquid, but soon hardens upon exposure to the air and sun, typically drying to an amber-like material that consists of dark red angular fragments, rarely larger than a pea. Freshly exuded kino is more effective than kino that has been on the tree for a long while, since the soluble portion can be more or less washed out and the action of the sun can alter their chemical composition[].

The heartwood is yellowish brown; the sapwood somewhat paler. The texture is moderately coarse. The wood is heavy, strong, hard, tough, very durable, resistant to termite attacks. It has a greasy nature which makes gluing difficult, takes a good polish. It has many commercial uses and is particularly valued for flooring (parquetry, dance floors), but also for heavy construction, furniture, railway sleepers, poles, posts, vehicles, and wheelwork[, , , , , ].
The wood is used for fuel[].

Propagation

Seed - surface sow late winter/early spring in a sunny position in a greenhouse[, , ]. Species that come from high altitudes appreciate 6 - 8 weeks cold stratification at 2°c[]. 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 early summer, the young trees being planted in their final positions in late spring of the following year. The seed has a long viability[].