''Allocasuarina huegeliana'', commonly known as rock sheoak or sighing sheoak, is a

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Casuarinaceae The Casuarinaceae are a family of dicotyledonous flowering plants placed in the order Fagales, consisting of four genera and 91 species of trees and shrubs native to eastern Africa, Australia, Southeast Asia, Malesia, Papuasia, and the Pacifi ...

. Endemic to

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

, it occurs mostly throughout the Wheatbelt region. It is now especially common on road verges, where it sometimes forms thickets.

Description

Rock sheoak is a

dioecious Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...

tree that grows to a height of . The dark coloured bark is longitudinally fissured. It has sparse foliage that forms a rounded outline. Sometimes it branches at ground level, but usually has a bole of a few metres. As with other ''

Allocasuarina ''Allocasuarina'' is a genus of trees in the flowering plant family Casuarinaceae. They are endemic to Australia, occurring primarily in the south. Like the closely related genus ''Casuarina'', they are commonly called sheoaks or she-oaks. Wi ...

'' species, the foliage consists of slender green branchlets informally referred to as "needles" but more correctly termed

cladode Phylloclades and cladodes are flattened, photosynthetic shoots, which are usually considered to be modified branches. The two terms are used either differently or interchangeably by different authors. ''Phyllocladus'', a genus of conifer, is name ...

s. These are segmented, and the true leaves are reduced to tiny teeth encircling each joint. Male trees have small brown flower spikes at the end of branchlets. Female trees bear small flowers on short branchlets of their own. The red to brown coloured flowers appear between May and January. Fertilised flowers develop egg-shaped cones about wide.

Classification

Rock Sheoak was first collected on Mount Brown near

York York is a cathedral city with Roman origins, sited at the confluence of the rivers Ouse and Foss in North Yorkshire, England. It is the historic county town of Yorkshire. The city has many historic buildings and other structures, such as a ...

in 1840 by

Ludwig Preiss Johann August Ludwig Preiss (21 November 1811 – 21 May 1883) was a German-born British botanist and zoologist. Early life Preiss was born in Herzberg am Harz. He obtained a doctorate, probably at Hamburg, then emigrated to Western Australia. ...

. The specific name ''huegeliana'' honours the

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

n naturalist Baron Carl von Huegel. The species was first described by the

botanist Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek wo ...

Friedrich Anton Wilhelm Miquel Friedrich Anton Wilhelm Miquel (24 October 1811 – 23 January 1871) was a Dutch botanist, whose main focus of study was on the flora of the Dutch East Indies. Early life Miquel was born in Neuenhaus and studied medicine at the University of Groni ...

as ''

Casuarina ''Casuarina'' is a genus of 17 tree species in the family Casuarinaceae, native to Australia, the Indian subcontinent, southeast Asia, islands of the western Pacific Ocean, and eastern Africa. It was once treated as the sole genus in the fami ...

huegeliana'' in 1845 as part of the

Johann Georg Christian Lehmann Johann Georg Christian Lehmann (25 February 1792 – 12 February 1860) was a German botanist. Born at Haselau, near Uetersen, Holstein, Lehmann studied medicine in Copenhagen and Göttingen, obtained a doctorate in medicine in 1813 and a doct ...

work ''Casuarinaceae. Plantae Preissianae'', it as later reclassified to the current genera by

Lawrence Alexander Sidney Johnson Lawrence Alexander Sidney Johnson FAA, (26 June 1925 – 1 August 1997) known as Lawrie Johnson, was an Australian taxonomic botanist. He worked at the Royal Botanic Gardens, Sydney, for the whole of his professional career, as a botanist (1948 ...

in 1982 in the work ''Notes on Casuarinaceae II'' published in the Journal of the Adelaide Botanic Gardens. The common name "rock sheoak" refers to its habitat, which often contains granite rocks. The alternative common name "sighing sheoak" alludes to the sound of the wind in the foliage.

Distribution

The species is common throughout south west Western Australia and to the north in the

Mid West The Midwestern United States, also referred to as the Midwest or the American Midwest, is one of four Census Bureau Region, census regions of the United States Census Bureau (also known as "Region 2"). It occupies the northern central part of ...

through the Wheatbelt, Peel,

South West The points of the compass are a set of horizontal, radially arrayed compass directions (or azimuths) used in navigation and cartography. A compass rose is primarily composed of four cardinal directions—north, east, south, and west—each sepa ...

, Great Southern and the southern Goldfields-Esperance regions. It is found as far north as the Murchison River extending through to the southern coastline although populations are fragmented. It grows in sandy to sandy-loam soils and is mostly associated with

granite Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...

substrate or outcrops. It is also used as host species in

Sandalwood Sandalwood is a class of woods from trees in the genus ''Santalum''. The woods are heavy, yellow, and fine-grained, and, unlike many other aromatic woods, they retain their fragrance for decades. Sandalwood oil is extracted from the woods for us ...

plantations''Sandalwood Guide for Farmers'' Forest Products Commission April 2007'

Cultivation

''A. huegeliana'' is a moderate to fast growing tree that is

nitrogen fixing Nitrogen fixation is a chemical process by which molecular nitrogen (), with a strong triple covalent bond, in the Atmosphere of Earth, air is converted into ammonia () or related nitrogenous compounds, typically in soil or aquatic systems but al ...

. It can be grown as a windbreak. The species thrives in well-drained soils but will do poorly in saline or poorly drained areas. The attractive and dense wood from the tree is used to make specialty furniture while the foliage is used by grazing stock as fodder. The species is

drought A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...

and

frost Frost is a thin layer of ice on a solid surface, which forms from water vapor in an above-freezing atmosphere coming in contact with a solid surface whose temperature is below freezing, and resulting in a phase change from water vapor (a gas) ...

tolerant but will be killed by fire. Trees can live up an age of over 15 years.

Notes

References

* * {{Taxonbar, from=Q4732990 huegeliana Rosids of Western Australia Fagales of Australia Plants described in 1845 Dioecious plants