Forest Red Gum
Eucalyptus tereticornis
The Forest Red Gum (Eucalyptus tereticornis) is a tall, stately evergreen tree widespread across eastern Australia, instantly recognizable by its smooth, powdery white to gray bark that sheds in irregular patches, often revealing striking patches of bluish, pinkish, or creamy new bark. One of the most adaptable and widely distributed eucalyptus species, it is an essential component of Australian ecosystems and a vital food tree for koalas.
• Reaches 20 to 45 meters tall with a straight trunk and spreading crown
• Smooth, powdery white to gray bark that sheds in patches
• One of the most important koala food trees in Australia
• Widespread across eastern Australia in a variety of habitats
• Widely planted globally for timber, fuelwood, and reforestation
• Highly adaptable to different soil types and rainfall regimes
Taxonomy
• Distributed from the tip of Cape York Peninsula in far northern Queensland south through New South Wales and into eastern Victoria
• Also found in Papua New Guinea and parts of Indonesia
• Found at elevations from sea level to approximately 1,000 meters
• Occurs in a wide range of habitats including open forests, woodlands, and along watercourses
• One of the most widely distributed eucalyptus species in eastern Australia
• The species name "tereticornis" means "with a tapering horn," referring to the shape of the flower buds
• Widely planted across the tropics and subtropics for timber, fuelwood, and land rehabilitation
• Major plantation species in India, Africa, and South America
• Also known as Blue Leaf Gum and Queensland Blue Gum in different parts of Australia
Bark:
• Smooth throughout, shedding in large, irregular patches
• White to pale gray, powdery to the touch
• Newly exposed bark may show patches of blue-gray, pink, or cream
• Occasionally develops a short stocking of rough bark at the very base
Leaves:
• Adult leaves alternate, narrowly lanceolate, 10 to 20 cm long and 1.5 to 3 cm wide
• Dull green to gray-green, often with a bluish tinge
• Distinctive dense, reticulate venation visible when held to light
• Strongly aromatic when crushed
• Juvenile leaves are broader, duller, and more blue-green
Flowers:
• Produced in axillary umbels of 7 to 11 flowers
• White, small, with numerous conspicuous stamens
• Bud caps are horn-shaped ("tereticornis" = tapering horn)
• Bloom in winter to spring
• Rich in nectar
Fruit:
• Small, woody, conical to hemispherical capsules, 5 to 10 mm
• Contain numerous tiny seeds
Form:
• 20 to 45 meters tall with trunk diameter 50 to 120 cm
• Trunk typically straight, comprising half or more of the tree height
• Crown moderately dense, spreading
Habitat:
• Occurs across a remarkably wide range of habitats — from coastal flats to inland woodlands
• Found in open forests, woodlands, and along watercourses
• Tolerates a wide range of soils including heavy clays, sandy loams, and alluvial soils
• Adaptable to different rainfall regimes — from 500 to 2,000 mm annually
Ecological interactions:
• One of the top koala food trees — foliage is heavily browsed by koalas throughout its range
• Flowers produce abundant nectar consumed by honeyeaters, lorikeets, flying foxes, gliders, and possums
• Hollows in old trees are essential nesting sites for cockatoos, parrots, owls, and marsupial gliders
• Bark provides roosting habitat for insectivorous bats
• Supports a rich community of insects
Growth:
• Fast-growing, adding 1.5 to 2.5 meters per year in height when young
• Long-lived — trees of 200+ years are common
• Develops a lignotuber (woody swelling at the base) that allows regeneration after fire
• Coppices readily from cut stumps
Site selection:
• Full sun
• Tolerates a wide range of soils from heavy clay to sandy loam
• Adaptable to various rainfall levels — from 500 to 2,000 mm
• Suitable for Australian native gardens, farm shelterbelts, and habitat corridors
Planting:
• Plant seedlings or tube stock during the wet season or after rain
• Prepare a well-drained planting hole
• Mulch around the base to suppress weeds
Care:
• Water during the first dry season to establish
• Very drought-tolerant once established
• Minimal pruning needed
• Monitor for Myrtle Rust and eucalyptus borers
• Hardy in USDA zones 9 to 11
Wildlife habitat:
• One of the most important koala food trees across eastern Australia
• Old trees with hollows are critical habitat for over 100 species of Australian wildlife
• Major nectar source for honey production
Timber:
• Hard, strong, durable wood — one of the most important Australian timber species
• Used for construction, flooring, fencing, railway sleepers, and poles
• Widely planted in India, Africa, and South America for timber and fuelwood
• Plantation-grown wood used for paper pulp and medium-density fiberboard
Essential oil:
• Leaves yield cineole-rich eucalyptus oil
• Used in medicinal products, antiseptics, and industrial solvents
Land rehabilitation:
• Widely planted for mine site rehabilitation, erosion control, and watershed protection
• Fast growth and soil-improving properties make it valuable for land restoration
Honey:
• Produces good-quality honey in sufficient quantities for commercial beekeeping
Fun Fact
The Forest Red Gum is one of the most important food trees for koalas in Australia, and old-growth Forest Red Gums with their hollow branches are the high-rise apartment buildings of the Australian bush. A single mature tree can provide nesting hollows for multiple species simultaneously — including cockatoos, owls, parrots, gliding possums, and microbats. The Australian government estimates that it takes 120 to 200 years for a eucalyptus to form suitable hollows, making every old Forest Red Gum irreplaceable habitat.
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