''Eucalyptus saligna'', commonly known as the Sydney blue gum or blue gum,
is a species of medium-sized to tall tree that is
endemic
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
to eastern Australia. It has rough, flaky bark near the base of the trunk, smooth bark above, lance-shaped to curved adult leaves, flower buds in groups of seven, nine or eleven, white flowers and cylindrical to conical or cup-shaped fruit.
Description
''Eucalyptus saligna'' is a tree with a straight trunk that typically grows to a height of , rarely to , a
dbh of , and forms 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 respons ...
. The trunk has smooth pale grey or white bark with of rough brownish bark at the base. Young plants and
coppice
Coppicing is the traditional method in woodland management of cutting down a tree to a tree stump, stump, which in many species encourages new Shoot (botany), shoots to grow from the stump or roots, thus ultimately regrowing the tree. A forest ...
regrowth have lance-shaped to egg-shaped or oblong leaves that are paler on the lower surface, long and wide. Adult leaves are arranged alternately, glossy green, paler on the lower surface, lance-shaped to curved, long and wide, on a
petiole
Petiole may refer to:
*Petiole (botany), the stalk of a leaf, attaching the blade to the stem
*Petiole (insect anatomy)
In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...
long. The flower buds are arranged in leaf
axil
A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, fl ...
s in groups of seven, nine or eleven on an unbranched
peduncle long, the individual buds
sessile or on
pedicels
In botany, a pedicel is a stem that attaches a single flower to the inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branch ...
up to long. Mature buds are spindle-shaped, oval or diamond-shaped, long and wide with a conical or beaked
operculum. Flowering occurs from December to March and the flowers are white. The fruit is a woody cylindrical, conical or cup-shaped
capsule long and wide with the valves protruding above the rim.
Taxonomy and naming
''Eucalyptus saligna'' was first formally described in 1797 by English naturalist James Edward Smith in ''Transactions of the Linnean Society of London
The Linnean Society of London is a learned society dedicated to the study and dissemination of information concerning natural history, evolution, and taxonomy. It possesses several important biological specimen, manuscript and literature collec ...
'', and still bears its original name.willow
Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions.
Most species are known ...
, though what attribute this is, is unclear.[ Retrieved 12-24-2011.] It has been classified in the subgenus ''Symphyomyrtus'', Section ''Latoangulatae'', Series ''Transversae'' (eastern blue gums) by Ian Brooker
Murray Ian Hill Brooker Order of Australia, AM (2 June 1934 – 25 June 2016), better known as Ian Brooker, was an Australian botanist. He was widely recognised as the leading authority on the genus ''Eucalyptus''.
Ian Brooker was born in Adelai ...
and David Kleinig. Its two closest relatives are the flooded gum ('' E. grandis'') and the mountain blue gum ('' E. deanei'').
Distribution and habitat
Sydney blue gum is generally found within of the coastline in its range from Sydney
Sydney is the capital city of the States and territories of Australia, state of New South Wales and the List of cities in Australia by population, most populous city in Australia. Located on Australia's east coast, the metropolis surrounds Syd ...
to Maryborough in central Queensland. To the northwest, it is found in disjunct populations in central Queensland, including in Eungella National Park, Kroombit Tops, Consuelo Tableland, Blackdown Tableland and Carnarvon Gorge
Carnarvon Gorge is located in the Southern Brigalow Belt bioregion in Central Queensland (Australia), 593 km northwest of Brisbane. Primarily created by water erosion, Carnarvon Gorge is around 30 kilometres long, located in Carnarvon Natio ...
.[ It is a component of the endangered ]blue gum high forest
The Blue Gum High Forest of the Sydney Basin Bioregion is a wet sclerophyll forest found in the northern parts of Sydney, New South Wales, Australia. It has been classified as critically endangered species, critically endangered, under the New Sou ...
ecological community in the Sydney region.[ Populations found south of Sydney are now not considered to be ''E. saligna''.]Angophora floribunda
''Angophora floribunda'', commonly known as the rough-barked apple, is a common woodland and forest tree of the family Myrtaceae native to Eastern Australia. Reaching 30 m (100 ft) high, it is a large tree with fibrous bark and cream-wh ...
''), spotted gum (''Corymbia maculata
''Corymbia maculata'', commonly known as spotted gum, is a species of medium-sized to tall tree that is Endemism, endemic to eastern Australia. It has smooth, mottled bark, lance-shaped to curved adult leaves, flower buds usually in groups of t ...
''), turpentine (''Syncarpia glomulifera
''Syncarpia glomulifera'', commonly known as the turpentine tree, or yanderra, is a tree of the family Myrtaceae native to New South Wales and Queensland in Australia, which can reach in height. It generally grows on heavier soils. The cream fl ...
''), brush box ('' Lophostemon confertus'') and forest oak (''Allocasuarina torulosa
''Allocasuarina torulosa'', commonly known as forest oak, rose sheoak, river oak or Baker's oak, is a species of flowering plant in the family Casuarinaceae and is endemic to eastern Australia. It is a slender, usually dioecious tree that has ...
'').[
South of ]Sydney Harbour
Port Jackson, commonly known as Sydney Harbour, is a ria, natural harbour on the east coast of Australia, around which Sydney was built. It consists of the waters of Sydney Harbour, Middle Harbour, North Harbour and the Lane Cove River, Lane ...
and the Parramatta River
The Parramatta River is an intermediate tide-dominated, Ria, drowned valley estuary located in Sydney, New South Wales, Australia. With an average Altitude, height, and depth, depth of , the Parramatta River is the main tributary of Sydney Harbour ...
, pure stands of ''E. saligna'' give way to hybrid populations with bangalay ('' E. botryoides'').
Ecology
''Eucalyptus saligna'' regenerates by regrowing from epicormic buds on the trunk and lower branches after bushfire. Trees live for over two hundred years. The grey-headed flying fox
The grey-headed flying fox (''Pteropus poliocephalus'') is a megabat native to Australia. The species shares mainland Australia with three other members of the genus ''Pteropus'': the little red '' P. scapulatus'', spectacled '' P. conspicillat ...
(''Pteropus poliocephalus'') eats the flowers, the koala
The koala (''Phascolarctos cinereus''), sometimes inaccurately called the koala bear, is an arboreal herbivorous marsupial native to Australia. It is the only Extant taxon, extant representative of the Family (biology), family ''Phascolar ...
(''Phascalarctos cinereus'') eats the leaves, and crimson rosella (''Platycercus elegans'') eats the seed.[ The ]longhorn beetle
The longhorn beetles (Cerambycidae), also known as long-horned or longicorns (whose larvae are often referred to as roundheaded borers), are a large family of beetles, with over 35,000 species described.
Most species are characterized by Antenn ...
species '' Paroplites australis'', '' Agrianome spinicollis'' and '' Tessaromma undatum'' have been recorded from the Sydney blue gum.[
The presence of the territorial and aggressive bell miner (''Manorina melanophrys'') and psyllid insects ('' Glycaspis'') is correlated with dieback of the canopy of ''E. saligna'', a syndrome which has been termed bell-miner-associated dieback (BMAD), though the exact mechanism remains unclear.][ Retrieved 12-24-2011.] After colonization by '' Glycaspis'', ''E. salinga'' may then be infested by the ambrosia beetle
Ambrosia beetles are beetles of the weevil subfamilies Scolytinae and Platypodinae (Coleoptera, Curculionidae), which live in nutritional symbiosis with ambrosia fungi. The beetles excavate tunnels in dead or stressed trees into which they introduc ...
'' Amasa truncata''.
Uses
The wood of this species is heavy (about 850 kg/m3), fairly hard, coarse, even textured
and reasonably easy to work. It is used for general building construction, panelling, and boatbuilding, and is highly prized for flooring and furniture because of its rich dark honey colour.[Bootle KR. (1983). ''Wood in Australia. Types, properties and uses.'' McGraw-Hill Book Company, Sydney. ]
File:Sydney Blue Gum (E.saligna) - stocking bark.jpg, Stocking bark
File:Sydney Blue Gum (E.saligna) - trunk bark.jpg, Trunk bark
File:Sydney Blue Gum (E.saligna) - bark shedding.jpg, Shedding bark
File:Sydney Blue Gum (E.saligna) - leaves.jpg, Leaves
File:Sydney Blue Gum (E.saligna) - buds.jpg, Buds
File:Eucalyptus saligna seeds00.jpg, Seeds
References
{{Authority control
saligna
Trees of Australia
Myrtales of Australia
Flora of New South Wales
Flora of Queensland
Plants described in 1797