''Alsophila australis'',

synonym A synonym is a word, morpheme, or phrase that means exactly or nearly the same as another word, morpheme, or phrase in a given language. For example, in the English language, the words ''begin'', ''start'', ''commence'', and ''initiate'' are al ...

''Cyathea australis'', also known as the rough tree fern, is a species of tree fern native to southeastern

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

and southern Victoria in Australia, as well as

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

and

Norfolk Island Norfolk Island (, ; Norfuk: ''Norf'k Ailen'') is an external territory of Australia located in the Pacific Ocean between New Zealand and New Caledonia, directly east of Australia's Evans Head and about from Lord Howe Island. Together w ...

. It was known by the aboriginal people of

Illawarra The Illawarra is a coastal region in the Australian state of New South Wales, nestled between the mountains and the sea. It is situated immediately south of Sydney and north of the South Coast region. It encompasses the two cities of Wollongo ...

as ''beeow-wang'', as ''pooeet'' at Corranderrk Station in Victoria, and as ''nanga-nanga'' in Queensland.

Taxonomy

''Alsophila australis'' was described in 1810 by Robert Brown from a specimen collected on King Island in

Bass Strait Bass Strait () is a strait separating the island state of Tasmania from the Australian mainland (more specifically the coast of Victoria, with the exception of the land border across Boundary Islet). The strait provides the most direct wat ...

, off the coast of Tasmania. It is the type for the genus '' Alsophila''. The specific

epithet An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ...

''australis'' means "southern" and refers to this southerly location. ''Alsophila australis'' is a highly variable

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

. Individuals from the

subspecies, ''A. australis'' ssp. ''norfolkensis'', are larger and more robust, differing primarily in scale characteristics. The subspecies is rare in cultivation. Further study is needed to determine whether this

represents a separate species or not.

Description

The massive erect trunk is usually up to 12 m tall, although specimens reaching 20 m have been reported from Queensland, Australia.

Frond A frond is a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group. Other botanists allow the term frond to also apply to the lar ...

s are bi- or tripinnate and may reach 4 m in length, occasionally even 6 m. These form a distinctive crown that is dark green above and lighter green below. It has quite adventitious roots, tubercles and hair-like follicles on its "trunk". Plants growing in southern Australia often lose their fronds by the end of winter, as is the case with ''

Alsophila dregei ''Alsophila dregei'', synonym ''Cyathea dregei'', (common tree fern or ''gewone boomvaring'' in Afrikaans) is a widespread species of tree fern in southern Africa. Within South Africa, it co-occurs with the indigenous forest tree fern (''A. ca ...

'' in

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring count ...

. Characteristically of this species, stipe bases are often retained around the trunk long after withering. They are covered with

scale Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number ...

s and conical, blunt spines towards the base. The scales range in colour from shiny brown to bicoloured (pale and brown) and are often distinctly twisted. The sori are circular and occur on either side of the fertile pinnule midvein. True indusia are absent, although reduced scales may encircle the sori. In its montane range, ''A. australis'' is ecologically important as it provides the nesting substrate for ''

Exoneura robusta ''Exoneura robusta'' is a species of the primitively eusocial Allodapini, allodapine bee, belonging to the genus commonly referred to as "reed bees". Their common name derives from their use of the soft pith of dead fern fronds as a nesting mater ...

'', a native species of reed bee. These bees almost exclusively build their nests in the pith of dead ''A. australis'' fronds. This species of bee is an important pollinator of other plants in southeastern Australia, so thus it can be seen how ''A. australis'' is indirectly supportive of other plants in its ecosystem.

Traditional use

Joseph Maiden recorded in 1889 that "The pulp of the top of the trunk is full of starch, and is eaten raw and roasted by the aboriginals. This whitish substance is found in the middle of the tree from the base to the apex, and when boiled tastes like a bad turnip. Pigs feed on it greedily."

Cultivation

''Alsophila australis'' is a robust tub plant and tolerant of salty winds. It is a popular cool climate hardy tree-fern, adaptable to a variety of climates and soils. It grows in moist shady forest, both coastal and montane, at an altitude of up to 1280 m, often in the company of ''

Dicksonia antarctica ''Dicksonia antarctica'', the soft tree fern or man fern, is a species of evergreen tree fern native to eastern Australia, ranging from south-east Queensland, coastal New South Wales and Victoria to Tasmania. Anatomy and biology These fern ...

''. It is a relatively hardy species and a popular landscape and container plant. Provided moisture levels remain high, it will tolerate frost and full sun, or shade in warmer regions. Although well known in its native country, this species is not common in cultivation outside of Australia.

Horticulture

In the

horticultural Horticulture is the branch of agriculture that deals with the art, science, technology, and business of plant cultivation. It includes the cultivation of fruits, vegetables, nuts, seeds, herbs, sprouts, mushrooms, algae, flowers, seaweeds and no ...

trade, most plants labeled as ''Alsophila australis'' are in fact '' Sphaeropteris cooperi''. Much confusion has existed between the two, especially in the United States, despite the two species being quite distinct from one another. ''A. australis'' is relatively stout trunked and has a large number of closely spaced fronds emerging at one time, with a slower increase in trunk height. ''S. cooperi'' in contrast, grows more quickly with fewer fronds emerging each year and has a much narrower trunk, with the frond bases aligned vertically for some distance ("hugging" the trunk as it were) before arching outwards.

References

UNEP-WCMC Species Database: ''Cyathea australis''
{{Taxonbar, from1=Q17185344, from2=Q738235 australis Flora of New South Wales Flora of Queensland Flora of Tasmania Flora of Victoria (Australia) Flora of Norfolk Island Ferns of Australia Trees of Australia Ornamental trees Trees of mild maritime climate Plants described in 1810