Common Name: Red Ironbark

General Information

Eucalyptus crebra is an evergreen tree with a rather open and straggly crown; it can grow 25 - 35 metres tall. Under good growing conditions the tree has straight bole that can be 70 - 150cm in diameter and unbranched for up to 25 metres[].
The tree is harvested from the wild for its wood, which is used commercially. This is one of three species of tree that produce a much sought-after, immensely strong and durable timber known as 'Red Ironbark'[].

Known Hazards

None known

Botanical References

, ,

Range

Australia - northern New South Wales, eastern Queensland.

Habitat

Commonly found on country of low relief, in higher rainfall areas it grows on ridges and higher slopes. Found at elevations from sea level to 1,400 metres[]. Grassy or sclerophyll woodland or forest on shallower or sandy soils of medium fertility[].

Properties

Other Uses Rating
Habit	Evergreen Tree
Height	30.00 m
Growth Rate	Medium
Pollinators	Bees, Insects
Cultivation Status	Wild

Cultivation Details

Eucalyptus crebra is a plant of the subtropical to tropical zones of eastern Australia where it can be found at elevations from sea level to 1,400 metres[]. It grows best in areas where annual daytime temperatures are within the range 26 - 36°c, but can tolerate 9 - 40°c[]. New growth can be killed by temperatures of -1°c or lower, whilst temperatures of -5°c can kill even the dormant plant[]. It prefers a mean annual rainfall in the range 600 - 2,000mm, but tolerates 500 - 2,400mm[].
Requires a sunny position. Prefers a light to medium, well-drained soil, succeeding in soils of low fertility[]. Found in the wild in a range of soils, but mainly acid sandy soils, sometimes overlying alkaline clayey subsoils[]. Prefers a pH in the range 5.5 - 6.5, tolerating 5 - 7.5[]. Established plants are drought tolerant[].
Trees are somewhat slow-growing[].
Annual wood production potential is 3 - 8 cubic metres per hectare[].
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[].
The tree has a thick, hard, corrugated bark[]. This species is one of the ironbark group of Eucalypts. The resin exudes into the bark then hardens making the bark very haed and difficult to cut through with primitive tools[].
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[].

Edible Uses

None known

Medicinal

None known

Agroforestry Uses:

The flowers are a very good source of nectar and pollen for bees[].

Other Uses

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 0.5 - 0.9% essential oil. The main components include 1,8-cineole (around 66% in one form) and pinene (around 26% in one form)[].

The heartwood is dark red; the sapwood yellowish[]. The wood is fine-textured; the grain usually interlocked; it is heavy, very hard, very strong, extremely durable and resistent to termite attack. Slow to dry, but does not collapse appreciably. An excellent timber, it is used for heavy engineering construction, poles, railway sleepers and cross arms[, , , , ].
The wood makes an excellent fuel and charcoal[].

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[].