''Eucalyptus diversifolia'', commonly known as the soap mallee, coastal white mallee, South Australian coastal mallee, or coast gum is a species of mallee that is

endemic Endemism is the state of a species being found 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 found else ...

to an area along the southern coast of Australia. It has smooth bark, lance-shaped adult leaves, flower buds in groups of between seven and eleven, white to creamy yellow flowers and cup-shaped fruit.

Description

''Eucalyptus diversifolia'' is a mallee that typically grows to a height 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 response t ...

. It has smooth, mainly cream-coloured and grey bark. Young plants and

coppice Coppicing is a traditional method of woodland management which exploits the capacity of many species of trees to put out new shoots from their stump or roots if cut down. In a coppiced wood, which is called a copse, young tree stems are repeate ...

regrowth 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 ...

, egg-shaped to elliptic leaves arranged in opposite pairs, long and wide. Adult leaves are arranged alternately, the same olive-green or bluish-green on both sides, lance-shaped, long and wide on a petiole long. The flower buds are arranged in groups of seven, nine or eleven in leaf axils on an unbranched peduncle long, the individual buds on a

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

long. Mature buds are diamond-shaped, long and wide with a conical to beaked operculum. Flowering occurs between July and September or December to January and the flowers are white to cream-yellow flowers. The fruit is a woody, cup-shaped capsule long and wide, sessile or on a pedicel up to long with the valves about level with the rim. The seeds are smooth glossy brown and pyramidal.

Taxonomy

''Eucalyptus diversifolia'' was first formally described by the botanist

Aimé Bonpland Aimé Jacques Alexandre Bonpland (; 22 August 1773 – 11 May 1858) was a French explorer and botanist who traveled with Alexander von Humboldt in Latin America from 1799 to 1804. He co-authored volumes of the scientific results of their ex ...

in 1814 and the description was published in his book ''Description des Plantes Rares cultivees a Malmaison et a Navarre''. Three subspecies were described in 1987 by

Ian Wright Ian Edward Wright (born 3 November 1963) is an English television and radio personality and former professional footballer. He works as a pundit for BBC Sport and ITV Sport. Wright enjoyed success with London clubs Crystal Palace and Arsenal ...

and

Pauline Ladiges Pauline Yvonne Ladiges (born 1948) is a botanist whose contributions have been significant both in building the field of taxonomy, ecology and historical biogeography of Australian plants, particularly Eucalypts and flora, and in science educa ...

and two of these are recognised by the

Australian Plant Census The Australian Plant Census (APC) provides an online interface to currently accepted, published, scientific names of the vascular flora of Australia, as one of the output interfaces of the national government Integrated Biodiversity Information Syst ...

(APC): * ''Eucalyptus diversifolia'' subsp. ''diversifolia'' has smooth bark and cup-shaped fruit less than in diameter; * ''Eucalyptus diversifolia'' subsp. ''hesperia'' has a short skirt of rough bark at the base and fruit that is usually smaller than in subspecies ''diversifolia''. ''Eucalyptus diversifolia'' subsp. ''megacarpa'' is regarded as a synonym of ''E. diversifolia'' subsp. ''diversifolia'' by the APC but is an accepted subspecies in Victoria and has fruit that is in diameter. This species is part of the ''Eucalyptus'' subgenus series ''Diversiformae'', a group of mallees that all have adult leaves held erect, buds with a single unscarred operculum and pyramidal seeds. The other species in this series include '' E. erectifolia'', '' E. platydisca'', '' E. pachyloma'', '' E. todtiana'', '' E. lateritica'', '' E. dolorosa'' and '' E. buprestium''. The specific epithet (''diversifolia'') is derived from the

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 ...

words ''diversus'' meaning "different" and ''folium'' meaning "leaf".Backer, C.A. (1936). ''Verklarend woordenboek der wetenschappelijke namen van de in Nederland en Nederlandsch-Indië in het wild groeiende en in tuinen en parken gekweekte varens en hoogere planten'' (Edition Nicoline van der Sijs).

Distribution

Soap mallee grows in soils derived from

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, often on exposed headlands. Subspecies ''diversifolia'' is found on the Eyre and lower

Yorke Peninsula The Yorke Peninsula is a peninsula located northwest and west of Adelaide in South Australia, between Spencer Gulf on the west and Gulf St Vincent on the east. The peninsula is separated from Kangaroo Island to the south by Investigator Str ...

s, on

Kangaroo Island Kangaroo Island, also known as Karta Pintingga (literally 'Island of the Dead' in the language of the Kaurna people), is Australia's third-largest island, after Tasmania and Melville Island. It lies in the state of South Australia, southwest ...

in South Australia and eastwards to the Cape Nelson State Park with an isolated population near Aireys Inlet in Victoria, but it is absent from the

Nullarbor Plain The Nullarbor Plain ( ; Latin: feminine of , 'no', and , 'tree') is part of the area of flat, almost treeless, arid or semi-arid country of southern Australia, located on the Great Australian Bight coast with the Great Victoria Desert to its ...

in far western South Australia. Subspecies ''hesperia'' occurs west of the Nullarbor Plain between Eucla, Caiguna, Cocklebiddy and

Madura Madura Island is an Indonesian island off the northeastern coast of Java. The island comprises an area of approximately (administratively 5,379.33 km2 including various smaller islands to the east, southeast and north that are administrati ...

Uses

This species is able to produce large amounts of biomass, making per hectare per year. In wheatbelt regions it is also beneficial as the tree will reduce salinity, give shade to stock, act as a windbreak and reduce

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is dis ...

Gallery

File:Eucalyptus diversifolia - adult leaves.jpg, adult leaves File:Eucalyptus diversifolia buds.jpg, flower buds and flowers File:Eucalyptus diversifolia fruit.jpg, buds and fruit File:Eucalyptus diversifolia - fruit.jpg, open fruit File:Eucalyptus diversifolia - trunk bark.jpg, bark

References