Jarrah
Encyclopedia
Eucalyptus marginata is one of the most common species of Eucalyptus
tree in the southwest
of Western Australia
. The tree and the wood are usually referred to by the Aboriginal name Jarrah. Because of the similar appearance of worked jarrah timber to the Honduras
mahogany
tree, jarrah was once called Swan River mahogany after the river system that runs through Perth
.
which sheds in long flat strips. The leaves
are often curved, 8–13 cm (3.1–5.1 in) long and 1.5–3 cm (0.590551181102362–1.2 in) broad, shiny dark green above and paler below. The species' scientific name marginata refers to the light-coloured vein on the border around its leaves. The stalked flower
buds appear in clusters of between 7 and 11; each bud has a narrow, conical bud cap 5–9 mm (0.196850393700787–0.354330708661417 in) long. The flowers are white, 1–2 cm (0.393700787401575–0.78740157480315 in) in diameter, and bloom in spring and early summer. The fruit
s are spherical to barrel-shaped, and 9–16 mm (0.354330708661417–0.62992125984252 in) long and broad.
The bark of this Eucalyptus is not shed in patches as it is with many others, but splits into fibrous strips. Jarrah trees are also unusual in that they have a lignotuber
, a large underground swelling which stores carbohydrates and allows young trees to regenerate after a fire. Because they are deep-rooted, as much as 40 metres (131.2 ft), jarrah are drought resistant and able to draw water from great depths during dry periods.
, providing numerous habitats for animal life - especially birds and bees - while it is alive, and in the hollows that form as the heartwood decays. When it falls, it provides shelter to ground-dwellers such as the chuditch (Dasyurus geoffroii), a carnivorous
marsupial
.
Jarrah has shown considerable adaptation to different ecologic zones - as in the Swan Coastal Plain
and further north, and also to a different habitat of the lateritic Darling Scarp
.
Jarrah is very vulnerable to "dieback", the oomycete Phytophthora cinnamomi
, which causes root-rot. In large sections of the Darling Scarp
there have been various measures to reduce the spread of dieback by washing down vehicles, and restricting access to areas of forest not yet infected.
of 1.1 when green. Its long, straight trunks of richly coloured and beautifully grained termite-resistant timber make it valuable for cabinet making, flooring, panelling and outdoor furniture. The finished timber has a deep rich reddish-brown colour and an attractive grain. When fresh, jarrah is quite workable but when seasoned it becomes so hard that conventional wood-working tools are useless. It is very durable, even in wet and weathered situations, making it a choice structural material for bridges, wharves, railway sleepers
, ship building and telegraph poles.
Jarrah wood is very similar to that of Karri, Eucalyptus diversicolor. Both trees are found in the south west of Australia, the two timbers are frequently confused. They can be distinguished by cutting an unweathered splinter and burning it: karri burns completely to a white ash, whereas jarrah forms charcoal. Most of the best jarrah has been cut out of south Western Australia.
A large amount was exported to the United Kingdom, where it was cut into blocks and covered with asphalt for roads. One of the large exporters in the late nineteenth century was M. C. Davies
who had mills in the Margaret River to Augusta region of the south west, and ports at Hamelin Bay and Flinders Bay
.
The local poet 'Dryblower Murphy'
wrote a poem in the early twentieth century about the potential to extract alcohol from jarrah timber "Comeanavajarrah", suggesting that the resource was an endless one for exploitation. Significantly most of the companies that exploited jarrah in the early twentieth century no longer exist.
Jarrah has become more highly prized, and supports an industry that recycles it from demolished houses. Even so, in 2004, old 4 by recycled jarrah is routinely advertised in Perth papers for under $1.50 per metre. Larger pieces of the timber were produced in the early history of the industry, from trees of great age, and these are also recovered from the demolition of older buildings.
Offcuts and millends, dead and fire affected jarrah also sell as firewood for those using wood for heating in Perth, and 1 tonnes (2,204.6 lb) loads can (as of Winter 2005) exceed $160 per load. Jarrah tends to work well in slow combustion stoves and closed fires and generates a greater heat than most other available woods.
Jarrah is used in musical instrument making, for percussion instruments and guitar inlays.
Because of its remarkable resistance to rot, jarrah is used to make hot tubs.
Eucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
tree in the southwest
Southwest Australia
Southwest Australia is a biodiversity hotspot that includes the Mediterranean forests, woodlands, and scrub ecoregions of Western Australia. The region has a wet-winter, dry-summer Mediterranean climate, one of five such regions in the world...
of Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
. The tree and the wood are usually referred to by the Aboriginal name Jarrah. Because of the similar appearance of worked jarrah timber to the Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
mahogany
Mahogany
The name mahogany is used when referring to numerous varieties of dark-colored hardwood. It is a native American word originally used for the wood of the species Swietenia mahagoni, known as West Indian or Cuban mahogany....
tree, jarrah was once called Swan River mahogany after the river system that runs through Perth
Perth, Western Australia
Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....
.
Description
The tree grows up to 40 metres (131.2 ft) high with a trunk up to 3 metres (9.8 ft) in diameter, and has rough, greyish-brown, vertically grooved, fibrous barkBark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
which sheds in long flat strips. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are often curved, 8–13 cm (3.1–5.1 in) long and 1.5–3 cm (0.590551181102362–1.2 in) broad, shiny dark green above and paler below. The species' scientific name marginata refers to the light-coloured vein on the border around its leaves. The stalked flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
buds appear in clusters of between 7 and 11; each bud has a narrow, conical bud cap 5–9 mm (0.196850393700787–0.354330708661417 in) long. The flowers are white, 1–2 cm (0.393700787401575–0.78740157480315 in) in diameter, and bloom in spring and early summer. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s are spherical to barrel-shaped, and 9–16 mm (0.354330708661417–0.62992125984252 in) long and broad.
The bark of this Eucalyptus is not shed in patches as it is with many others, but splits into fibrous strips. Jarrah trees are also unusual in that they have a lignotuber
Lignotuber
A lignotuber is a starchy swelling of the root crown possessed by some plants as a protection against destruction of the plant stem by fire. The crown contains buds from which new stems may sprout, and a sufficient store of nutrients to support a period of growth in the absence of...
, a large underground swelling which stores carbohydrates and allows young trees to regenerate after a fire. Because they are deep-rooted, as much as 40 metres (131.2 ft), jarrah are drought resistant and able to draw water from great depths during dry periods.
Ecology
Jarrah is an important element in its ecologyEcology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...
, providing numerous habitats for animal life - especially birds and bees - while it is alive, and in the hollows that form as the heartwood decays. When it falls, it provides shelter to ground-dwellers such as the chuditch (Dasyurus geoffroii), a carnivorous
Carnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
marsupial
Marsupial
Marsupials are an infraclass of mammals, characterized by giving birth to relatively undeveloped young. Close to 70% of the 334 extant species occur in Australia, New Guinea, and nearby islands, with the remaining 100 found in the Americas, primarily in South America, but with thirteen in Central...
.
Jarrah has shown considerable adaptation to different ecologic zones - as in the Swan Coastal Plain
Swan Coastal Plain
The Swan Coastal Plain in Western Australia is the geographic feature which contains the Swan River as it travels west to the Indian Ocean. The coastal plain continues well beyond the boundaries of the Swan River and its tributaries, as a geological and biological zone, one of Western Australia's...
and further north, and also to a different habitat of the lateritic Darling Scarp
Darling Scarp
The Darling Scarp, also referred to as the Darling Range or Darling Ranges, is a low escarpment running north-south to the east of the Swan Coastal Plain and Perth, Western Australia...
.
Jarrah is very vulnerable to "dieback", the oomycete Phytophthora cinnamomi
Phytophthora cinnamomi
Phytophthora cinnamomi is a soil-borne water mould that produces an infection which causes a condition in plants called root rot or dieback. The plant pathogen is one of the world's most invasive species and is present in over 70 countries from around the world.- Life cycle and effects on plants :P...
, which causes root-rot. In large sections of the Darling Scarp
Darling Scarp
The Darling Scarp, also referred to as the Darling Range or Darling Ranges, is a low escarpment running north-south to the east of the Swan Coastal Plain and Perth, Western Australia...
there have been various measures to reduce the spread of dieback by washing down vehicles, and restricting access to areas of forest not yet infected.
Uses
Jarrah flowers are used to make honey, but its wood is its main use. It is a heavy timber, with a specific gravitySpecific gravity
Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...
of 1.1 when green. Its long, straight trunks of richly coloured and beautifully grained termite-resistant timber make it valuable for cabinet making, flooring, panelling and outdoor furniture. The finished timber has a deep rich reddish-brown colour and an attractive grain. When fresh, jarrah is quite workable but when seasoned it becomes so hard that conventional wood-working tools are useless. It is very durable, even in wet and weathered situations, making it a choice structural material for bridges, wharves, railway sleepers
Railroad tie
A railroad tie/railway tie , or railway sleeper is a rectangular item used to support the rails in railroad tracks...
, ship building and telegraph poles.
Jarrah wood is very similar to that of Karri, Eucalyptus diversicolor. Both trees are found in the south west of Australia, the two timbers are frequently confused. They can be distinguished by cutting an unweathered splinter and burning it: karri burns completely to a white ash, whereas jarrah forms charcoal. Most of the best jarrah has been cut out of south Western Australia.
A large amount was exported to the United Kingdom, where it was cut into blocks and covered with asphalt for roads. One of the large exporters in the late nineteenth century was M. C. Davies
M. C. Davies
Maurice Coleman Davies was a timber miller in the early history of Western Australia. He created the M.C.Davies Karri and Jarrah Timber Company, a timber empire that employed hundreds of men, laid over a hundred kilometres of private railway, and even built its own private ports for exporting of...
who had mills in the Margaret River to Augusta region of the south west, and ports at Hamelin Bay and Flinders Bay
Flinders Bay
Flinders Bay is a bay and locality that is immediately south of the townsite of Augusta, Western Australia, and close to the mouth of the Blackwood River and lies to the north east of Cape Leeuwin.-Bay:Flinders Bay...
.
The local poet 'Dryblower Murphy'
Edwin Greenslade Murphy
Edwin Greenslade Murphy, , was an Australian journalist and poet....
wrote a poem in the early twentieth century about the potential to extract alcohol from jarrah timber "Comeanavajarrah", suggesting that the resource was an endless one for exploitation. Significantly most of the companies that exploited jarrah in the early twentieth century no longer exist.
Jarrah has become more highly prized, and supports an industry that recycles it from demolished houses. Even so, in 2004, old 4 by recycled jarrah is routinely advertised in Perth papers for under $1.50 per metre. Larger pieces of the timber were produced in the early history of the industry, from trees of great age, and these are also recovered from the demolition of older buildings.
Offcuts and millends, dead and fire affected jarrah also sell as firewood for those using wood for heating in Perth, and 1 tonnes (2,204.6 lb) loads can (as of Winter 2005) exceed $160 per load. Jarrah tends to work well in slow combustion stoves and closed fires and generates a greater heat than most other available woods.
Jarrah is used in musical instrument making, for percussion instruments and guitar inlays.
Because of its remarkable resistance to rot, jarrah is used to make hot tubs.
See also
- Eucalyptus patensEucalyptus patensThe eucalyptus tree Eucalyptus patens has been known as yarri, blackbutt, Swan River blackbutt and Western Australia blackbutt....
- Jarrah forestJarrah forestJarrah forest is tall open forest in which the dominant overstory tree is Eucalyptus marginata . The ecosystem occurs only in the Southwest Botanical Province of Western Australia...
- Jarrah-Karri forest and shrublands