''Eucalyptus nitens'', commonly known as shining gum or silvertop, is a species of tall tree native to Victoria and eastern New South Wales. It has smooth greyish bark, sometimes with thin, rough bark near the base, lance-shaped adult leaves, flower buds in groups of seven or nine, white flowers and cup-shaped, barrel-shaped or cylindrical fruit. It grows in wet forests and rainforest margins on fertile soils in cool, high-rainfall areas.

Description

''Eucalyptus nitens'' is a tree that typically grows to a height of , sometimes to in Victoria, and does not form a

lignotuber A lignotuber is a woody swelling of the root crown possessed by some plants as a protection against destruction of the plant stem, such as by fire. Other woody plants may develop basal burls as a similar survival strategy, often as a response t ...

. It has smooth white, grey or yellow bark, often with persistent, rough, fibrous or flaky greyish bark near the base. The smooth bark is shed in long ribbons. Young plants have

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

leaves arranged in opposite pairs, lance-shaped to egg-shaped or heart-shaped, long and wide with stem-clasping bases. Adult leaves are lance-shaped to curved, glossy green, sometimes slightly paler on the lower surface, long and wide, tapering to a petiole long. The flower buds are arranged in leaf axils in groups of seven on an unbranched peduncle long, the individual buds sessile. Mature buds are oval or cylindrical, long and wide with a conical operculum that is the same width as the floral cup but shorter than it. Flowering occurs from January to March and the flowers are white. The fruit is a woody cylindrical, cup-shaped or barrel-shaped capsule long and wide with the valves near rim level.Boland, D. J. ''et al.'': Forest Trees of Australia. CSIRO Publishing, CollingwoodBrooker, M. I. H. & Kleinig, D. A. 2006: Field Guide to Eucalypts, Volume 1 South-eastern Australia. Bloomings Books, Melbourne

Taxonomy and naming

Shining gum was first formally described in 1899 by Henry Deane and

Joseph Maiden Joseph Henry Maiden (25 April 1859 – 16 November 1925) was a botanist who made a major contribution to knowledge of the Australian flora, especially the genus ''Eucalyptus''. This botanist is denoted by the author abbreviation when citing ...

, who gave it the name ''Eucalyptus goniocalyx'' var. ''nitens'' and published the description in '' Proceedings of the Linnean Society of New South Wales''. In 1913, Maiden raised the variety to species status as ''E. nitens'', publishing the change in his book, ''A Critical Revision of the Genus Eucalyptus''. The specific epithet (''nitens'') is a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

word meaning "shining", referring to the leaves, flower buds, fruit and bark of this species.

Distribution

''Eucalyptus nitens'' occurs in Victoria on ranges east and north-east of Melbourne at high altitudes on the east of the Great Dividing Range from the Blue Range, Mt Monda and Mt Torbreck eastwards. It is also found on the high tablelands and mountains of southern New South Wales. There are two widely disjunct populations at high altitude (around ) at

Barrington Tops Barrington Tops is part of the Great Dividing Range in New South Wales, Australia, between Gloucester and Scone. In 1934, the area was difficult to access and was described as being "not traceable to any man-made feature". Part of the area has ...

and near Ebor in north eastern New South Wales.

Uses

Tasmania ) , nickname = , image_map = Tasmania in Australia.svg , map_caption = Location of Tasmania in AustraliaCoordinates: , subdivision_type = Country , subdi ...

''Eucalyptus nitens'' is one of the most important

plantation A plantation is an agricultural estate, generally centered on a plantation house, meant for farming that specializes in cash crops, usually mainly planted with a single crop, with perhaps ancillary areas for vegetables for eating and so on. The ...

tree species along with ''

Eucalyptus globulus ''Eucalyptus globulus'', commonly known as southern blue gum or blue gum, is a species of tall, evergreen tree endemic to southeastern Australia. This ''Eucalyptus'' species has mostly smooth bark, juvenile leaves that are whitish and waxy on ...

'' (Tasmanian blue gum) and ''

Pinus radiata ''Pinus radiata'' ( syn. ''Pinus insignis''), the Monterey pine, insignis pine or radiata pine, is a species of pine native to the Central Coast of California and Mexico ( Guadalupe Island and Cedros island). It is an evergreen conifer in the ...

'' (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.VWA page
Victorian Woodworkers Association

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 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, anti ...

, 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.

References

{{Taxonbar, from=Q2512644 nitens Trees of Australia Trees of mild maritime climate Myrtales of Australia Flora of New South Wales Flora of Victoria (Australia)