Eucalyptus nitens
Encyclopedia
Eucalyptus nitens, commonly known as Shining Gum, is a Eucalypt species
native to Victoria
and eastern New South Wales
, Australia
. It grows in wet forest
s and rainforest
margins on fertile soil
s in cool high-rainfall areas.
tree
growing to 60 m, in Victoria occasionally to 90 m tall. Bark
is persistent on lower trunk, grey to grey-brown, fibrous-flaky, smooth above, white, grey or yellow, shedding in long ribbons. The juvenile leaves
are opposite, ovate to elliptic, cordate, glaucous
, and the adult leaves narrow-lanceolate or lanceolate, 15–25 cm long, 1.5–2.5 cm wide, green, glossy, concolorous. The inflorescence
is 7 flowered, the peduncle
narrowly flattened or angular, 6–15 mm long. Bud
s are sessile
, ovoid or cylindrical, 5–7 mm long, 3–4 mm in diameter, the ring scar caused by shedding of outer operculum
is present; the calyptra
is conical, acute or obtuse, shorter than and as wide as hypanthium
. The fruit
is cylindrical or ovoid, 4–7 mm long, 4–6 mm in diameter; the disc is depressed and the valves enclosed or rim-level.
Eucalyptus nitens is one of the most important plantation
tree species along with Eucalyptus globulus
(Tasmanian Blue Gum) and Pinus radiata (Monterey Pine). The timber is mainly used in general construction but is beginning to be used in furniture where the discolourations may be a feature.
, which is extracted from the leaves of eucalypts, is known to be toxic and have antiseptic properties.
Toxicological studies (in six laboratories) reported on the Australian Broadcasting Corporation's Australian Story program Feb 2010 found that the surface scum (foam) collected from a river supplying water to a Tasmanian town kills water fleas, mollusc larvae and human cell lines, and it was reported on the same program that "a large increase in cancer sufferers and a lot of people with rheumatoid arthritis, scleroderma, lupus" might have the same cause. However, studies commissioned by the Tasmanian Department of Health and Human Services found no reliable evidence that people who source water from this river are less healthy than people living elsewhere. Furthermore, although the Australian Story programs implied that Eucalyptus nitens plantations were the source of the toxins (which initiated widespread claims that such plantations represented 'toxic plantations' or 'poisonous plantations'), foam samples from native forest catchments devoid of both plantations and Eucalyptus nitens had previously been found to be similarly toxic. These natural toxins are highly concentrated (approximately 1400 fold) in river foam.
The claims and all available scientific data relating to the issue were reviewed by an Environment Protection Authority appointed group (established by Premier Bartlett) of eminent scientists from the University of Tasmania, Griffith University, Monash University and CSIRO in the first half of 2010. It was conclusively found by them that the water quality of the George River is of excellent standard, the cancer rates within the catchment are no higher than the Tasmanian average, and that any concern raised regarding the toxins in water foam was largely due to erroneous sampling techniques in the aforementioned toxicological studies. In June 2011 an internal ABC investigation found that the programs in question fell short of ABC editorial standards relating to contextual accuracy and balance.
After the Australian Story went to air the Tasmanian Director of Public Health, Dr Roscoe Taylor, had had an activated carbon purification system added to the St Helens water treatment plant. Dr Taylor stated at the time of its installation that "No scientific evidence has been presented to confirm the drinking water in St Helens was unsafe for human health before this precaution was taken". The filter was not removed after the review panel published its report.
The rebuttal of the George River Water's Panels deliberations on the scientists research and findings (NIWA's scientist,Dr Chris Hickey) sent to the ABC in July 2010 was posted on the ABC website at the time of the ABC's managing director's statement in June 2011.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
native to Victoria
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
and eastern New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
. It grows in wet forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s and rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
margins on fertile soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
s in cool high-rainfall areas.
Description
Eucalyptus nitens is a tall to very tall forestForest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
growing to 60 m, in Victoria occasionally to 90 m tall. Bark
Bark
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...
is persistent on lower trunk, grey to grey-brown, fibrous-flaky, smooth above, white, grey or yellow, shedding in long ribbons. The juvenile 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 opposite, ovate to elliptic, cordate, glaucous
Glaucous
Glaucous is used to describe the pale grey or bluish-green appearance of the surfaces of some plants, as well as in the names of birds, such as the Glaucous Gull , Glaucous-winged Gull , Glaucous Macaw , and Glaucous...
, and the adult leaves narrow-lanceolate or lanceolate, 15–25 cm long, 1.5–2.5 cm wide, green, glossy, concolorous. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is 7 flowered, the peduncle
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
narrowly flattened or angular, 6–15 mm long. Bud
Bud
In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of the stem. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specialized to develop flowers or short shoots, or may have...
s are sessile
Sessility (botany)
In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...
, ovoid or cylindrical, 5–7 mm long, 3–4 mm in diameter, the ring scar caused by shedding of outer operculum
Operculum (botany)
An operculum, in botany, is a term generally used to describe a structure within a plant, moss, or fungus acting as a cap, flap, or lid. In plants, it may also be called a bud cap.Examples of structures identified as opercula include:...
is present; the calyptra
Calyptra
Calyptra is a scientific term used in botany. It describes a feature in plant morphology.-Bryophytes:In bryophytes, the calyptra is an enlarged archegonial venter that protects the capsule containing the embryonic sporophyte . The calyptra is usually lost before the spores are released from the...
is conical, acute or obtuse, shorter than and as wide as hypanthium
Hypanthium
A hypanthium is a floral structure consisting of the bases of the sepals, petals, and stamens fused together. Its presence is diagnostic of many families, including the Rosaceae, Grossulariaceae, and Fabaceae...
. 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,...
is cylindrical or ovoid, 4–7 mm long, 4–6 mm in diameter; the disc is depressed and the valves enclosed or rim-level.
Uses
In TasmaniaTasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
Eucalyptus nitens is one of the most important plantation
Plantation
A plantation is a long artificially established forest, farm or estate, where crops are grown for sale, often in distant markets rather than for local on-site consumption...
tree species along with Eucalyptus globulus
Eucalyptus globulus
The Tasmanian Blue Gum, Southern Blue Gum or Blue Gum, is an evergreen tree, one of the most widely cultivated trees native to Australia. They typically grow from 30 to 55 m tall. The tallest currently known specimen in Tasmania is 90.7 m tall...
(Tasmanian Blue Gum) and Pinus radiata (Monterey Pine). The timber is mainly used in general construction but is beginning to be used in furniture where the discolourations may be a feature.
Possible Toxicity
Extracts from Eucalyptus nitens leaves have been found to be toxic to mollusc larvae. However, this study did not compare the toxicity of Eucalyptus nitens with other species and it is not known if it is any more or less toxic than other eucalypts. Eucalyptus oilEucalyptus oil
Eucalyptus oil is the generic name for distilled oil from the leaf of Eucalyptus, a genus of the plant family Myrtaceae native to Australia and cultivated worldwide. Eucalyptus oil has a history of wide application, as a pharmaceutical, antiseptic, repellent, flavouring, fragrance and industrial uses...
, which is extracted from the leaves of eucalypts, is known to be toxic and have antiseptic properties.
Toxicological studies (in six laboratories) reported on the Australian Broadcasting Corporation's Australian Story program Feb 2010 found that the surface scum (foam) collected from a river supplying water to a Tasmanian town kills water fleas, mollusc larvae and human cell lines, and it was reported on the same program that "a large increase in cancer sufferers and a lot of people with rheumatoid arthritis, scleroderma, lupus" might have the same cause. However, studies commissioned by the Tasmanian Department of Health and Human Services found no reliable evidence that people who source water from this river are less healthy than people living elsewhere. Furthermore, although the Australian Story programs implied that Eucalyptus nitens plantations were the source of the toxins (which initiated widespread claims that such plantations represented 'toxic plantations' or 'poisonous plantations'), foam samples from native forest catchments devoid of both plantations and Eucalyptus nitens had previously been found to be similarly toxic. These natural toxins are highly concentrated (approximately 1400 fold) in river foam.
The claims and all available scientific data relating to the issue were reviewed by an Environment Protection Authority appointed group (established by Premier Bartlett) of eminent scientists from the University of Tasmania, Griffith University, Monash University and CSIRO in the first half of 2010. It was conclusively found by them that the water quality of the George River is of excellent standard, the cancer rates within the catchment are no higher than the Tasmanian average, and that any concern raised regarding the toxins in water foam was largely due to erroneous sampling techniques in the aforementioned toxicological studies. In June 2011 an internal ABC investigation found that the programs in question fell short of ABC editorial standards relating to contextual accuracy and balance.
After the Australian Story went to air the Tasmanian Director of Public Health, Dr Roscoe Taylor, had had an activated carbon purification system added to the St Helens water treatment plant. Dr Taylor stated at the time of its installation that "No scientific evidence has been presented to confirm the drinking water in St Helens was unsafe for human health before this precaution was taken". The filter was not removed after the review panel published its report.
The rebuttal of the George River Water's Panels deliberations on the scientists research and findings (NIWA's scientist,Dr Chris Hickey) sent to the ABC in July 2010 was posted on the ABC website at the time of the ABC's managing director's statement in June 2011.