''Acacia merrallii'', commonly known as Merrall's wattle,
is a shrub belonging to the genus ''
Acacia
''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus na ...
'' and the subgenus ''Phyllodineae'' that is endemic to south western and southern
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
.
Description
The shrub typically grows to a height of
[ with a width ][ and can have a dense, rounded or spreading habit. The branchlets are often covered in minutely fine, straight or barely curved hairs. Like most species of ''Acacia'' it has ]phyllode
Phyllodes are modified petioles or leaf stems, which are leaf-like in appearance and function. In some plants, these become flattened and widened, while the leaf itself becomes reduced or vanishes altogether. Thus the phyllode comes to serve the ...
s rather than true leaves. The thick, smooth, grey-green phyllodes have an obliquely obovate to oblong-elliptic shape and is occasionally ovate. The phyllodes have a length of and a width of and are mostly slightly undulate with an obscure midrib and prominent margins.[ It blooms from August to October and produces yellow flowers.][ The rudimentary ]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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...
s are found on one to three headed racemes with a length of up to . The spherical flower-heads have a diameter of and contain 22 to 35 golden coloured flowers. The bow shaped to irregularly coiled seed pod
This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnify ...
s that form after flowering have a length of up to and a width of . The dark brown to black coloured glabrous pods are thinly coriaceous-crustaceous. The seeds inside are arranged longitudinally and are up to in length with a conspicuous orange coloured aril
An aril (pronounced ), also called an arillus, is a specialized outgrowth from a seed that partly or completely covers the seed. An arillode or false aril is sometimes distinguished: whereas an aril grows from the attachment point of the see ...
.[
]
Taxonomy
The species was first formally described by the botanist Ferdinand von Mueller
Baron Sir Ferdinand Jacob Heinrich von Mueller, (german: Müller; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Vict ...
in 1890 as part of the work ''Descriptions of hitherto unrecorded Australian plants, with additional phyto-geographic notes'' as published in the ''Proceedings of the Linnean Society of New South Wales''. It was reclassified as ''Racosperma merrallii'' in 2003 by Leslie Pedley
Leslie Pedley (19 May 1930 – 27 November 2018)IPNILeslie Pedley/ref> was an Australian botanist who specialised in the genus ''Acacia''. He is notable for bringing into use the generic name ''Racosperma'', creating a split in the genus, which r ...
then transferred back to genus ''Acacia'' in 2006. The only other synonyms are ''Acacia merrallii'' var. ''merrallii'' and ''Acacia dubia''.
Distribution
In Western Australia it is native to an area in the Goldfields-Esperance and Wheatbelt regions of 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 ...
where it is commonly situated on plains, low-lying areas and around salt lakes where it grows in sandy clay, sandy, loamy, calcareous or lateritic
Laterite is both a soil and a rock type rich in iron and aluminium and is commonly considered to have formed in hot and wet tropical areas. Nearly all laterites are of rusty-red coloration, because of high iron oxide content. They develop by ...
soils.Pingrup
Pingrup is a small town in the Great Southern (Western Australia), Great Southern region of Western Australia.
The name of the town is Indigenous Australian in origin and was the name of a lake that is close to the townsite. The meaning of Ping ...
in the south west extending out to around 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 ...
in the east. It is also found in South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...
along coastal areas of 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 ...
to around Moonta in the north east and Maitland
Maitland is an English and Scottish surname. It arrived in Britain after the Norman conquest of 1066. There are two theories about its source. It is either a nickname reference to "bad temper/disposition" (Old French, ''Maltalent''; Anglo Norm ...
in the south east on the 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 Strai ...
.[
]
Cultivation
The shrub is available commercially where it can be planted as an ornamental plant suitable for low maintenance areas where it can be employed as an understorey shrub in mixed plantings and along roadside verges or on median strip
The median strip, central reservation, roadway median, or traffic median is the reserved area that separates opposing lanes of traffic on divided roadways such as divided highways, dual carriageways, freeways, and motorways. The term also a ...
s as a wind-break, natural barrier or erosion control
Erosion control is the practice of preventing or controlling wind or water erosion in agriculture, land development, coastal areas, river banks and construction. Effective erosion controls handle surface runoff and are important techniques in ...
. It can be planted close to the coast line or in hills or on plains in full sun or part shade and can tolerate 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 moderate 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) ...
s. It is both bird and insect attracting.
See also
* List of ''Acacia'' species
References
{{Taxonbar, from=Q9566895
merrallii
Acacias of Western Australia
Taxa named by Ferdinand von Mueller
Flora of South Australia
Plants described in 1890