Coolabah, Coolibah, Flooded Box, Coolibah
Eucalyptus microtheca

Family: Myrtaceae

What it is like

Small to medium tree that can grow large in optimum conditions. Tolerates flooding, heavy soils, alkaline soils and a hot dry site. Great shade tree on larger properties.

Eucalyptus microtheca is an evergreen Tree growing to 15 m (49ft) by 10 m (32ft) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 9. The flowers are pollinated by Insects, Birds. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in heavy clay and nutritionally poor soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very alkaline soils. It cannot grow in the shade. It prefers moist soil. The plant can tolerate maritime exposure.

Height (m): 15

Where it is found

Usually found on seasonally inundated country around the edges of swamps or lagoons, or along watercourses.

Australia - South Australia, New South Wales, Queensland, Northern Territory, Western Australia.

Conservation Status: This taxon has not yet been assessed

Countries/locations it is found in

Africa, Asia, Australia, India, Iran, Iraq, Morocco, North Africa, Pakistan, Sudan, Tunisia, USA,

How it is used

Food

Rating: 2

The seeds are powdered and made into cakes which are baked and eaten. Sap from the roots is used as an emergency source of water for travellers through dry regions. The plant is a source of 'lerp' - a sweet, manna-like substance. Lerps are waxy scale-like coverings constructed by the immature stage (nymphs) of several species of sap-sucking insects. They serve as a protection whilst the nymphs are feeding and are left behind when the insect pupates. They were a traditional food of the Australian Aborigines.

Medicine

Rating: 0

Other

Rating: 2

The heartwood is reddish-brown or reddish; the sapwood is grey. The wood is remarkably hard, heavy and elastic. It is useful in construction, though perhaps too hard for cabinet-work; it is used for durable poles, fenceposts, bearings, bolts, shafts, frames and wheels. It is neither very much used nor valued. The wood is used for fuel and to make charcoal. The trees have a dense, rounded shape making them wind resistant and useful as windbreaks and to control erosion. They are one of the more commonly planted eucalyptus species in the southwestern United States since they are fast and easy to grow. Able to tolerate full sun, withstand temperatures below freezing and grow in soils with poor fertility makes them easy to grow.

Global Crop: These crops are already grown or traded around the world. The annual value of each is more than $1 billion US Examples include coconuts, almonds, and bananas.

Industrial Crop: Biomass: Three broad categories: bamboos, resprouting woody plants, and giant grasses. uses include: protein, materials (paper, building materials, fibers, biochar etc.), chemicals (biobased chemicals), energy - biofuels

Management: Coppice: Cut to the ground repeatedly - resprouting vigorously. Non-destructive management systems maintaining the soil organic carbon.

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Other Systems: SRC: Short-rotation coppice.

Global Crop: These crops are already grown or traded around the world. The annual value of each is more than $1 billion US Examples include coconuts, almonds, and bananas.

Industrial Crop: Biomass: Three broad categories: bamboos, resprouting woody plants, and giant grasses. uses include: protein, materials (paper, building materials, fibers, biochar etc.), chemicals (biobased chemicals), energy - biofuels

Management: Coppice: Cut to the ground repeatedly - resprouting vigorously. Non-destructive management systems maintaining the soil organic carbon.

Management: Standard: Plants grow to their standard height. Harvest fruit, seeds, or other products. Non-Destructive management systems.

Other Systems: SRC: Short-rotation coppice.

Carbon Farming: Plants that can be a critical part of the solution to climate problems. The Carbon Farming Solution - Eric Toensmeier.

How it is grown

A plant of the arid and semiarid tropics and subtropics, where it is found at elevations up to 1,000 metres. It grows best in areas where annual daytime temperatures are within the range 24 - 39?c, but can tolerate 5 - 45?c. It can be killed by temperatures of -4?c or lower, though new growth will be damaged if the temperature falls to zero. It prefers a mean annual rainfall in the range 250 - 1,---mm, but tolerates 150 - 1,200mm. Requires a sunny position. Succeeds in most soils of at least moderate fertility. Prefers a pH in the range 6.5 - 8, tolerating 6 - 9. The plant often experiences inundation for part of the year and is also able to withstand up to 7 months drought. A potentially very fast-growing species if there is sufficient water, on suitable sites the growth may reach 3 metres per year. Under irrigation it should be possible to grow the tree in deserts. The tree can be harvested after 8 years from a seedling crop and after 6 years from subsequent coppice crops. Annual wood production potential is 3 - 7 m3/ha. The tree is fire tender. 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. 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. Eucalyptus monocultures are an environmental disaster, they are voracious, allelopathic and encourage the worst possible attitudes to land use and conservation. E. microtheca is most closely related to the widespread Eucalyptus coolabah which is found in similar but drier habitats to the south and south-east It is also closely related to Eucalyptus victrix which is found in even drier habitats from central Australia west to the Pilbara region of Western Australia. Drought tolerant once established

Propagating it: Seed - surface sow in a sunny position and make sure the compost is not allowed to dry out. 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. The seedlings are ready for planting in the field when they are 25 - 30 cm tall, usually after 3 - 4 months. The seed has a long viability.

Best place to grow:

Habit: Tree

Hardiness: 9-12

Growth: Fast

Soil: Light (sandy), medium, heavy (clay)

Shade: No shade

Moisture: Moist

Things to keep in mind

Citronellal, an essential oil found in most Eucalyptus species is reported to be mutagenic when used in isolation. In large doses, oil of eucalyptus, like so many essential oils has caused fatalities from intestinal irritation. Death is reported from ingestion of 4 - 24 ml of essential oils, but recoveries are also reported for the same amount. 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.

Its other names

Local names

Coolabah. Coolibah

Synonyms

Eucalyptus raveretiana jerichoensis Domin