Dicksonia antarctica | |
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Gippsland, Australia. | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Division: | Polypodiophyta |
Class: | Polypodiopsida |
Order: | Cyatheales |
Family: | Dicksoniaceae |
Genus: | Dicksonia |
Species: | D. antarctica |
Binomial name | |
Dicksonia antarctica Labill. 1807 | |
Dicksonia antarctica, the soft tree fern, Tasmanian 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.
These ferns can grow to 15 m (49 ft) in height, but more typically grow to about 4.5–5 m (15–16 ft), and consist of an erect rhizome forming a trunk. They are very hairy at the base of the stipe (adjoining the trunk) and on the crown. The large, dark green, roughly-textured fronds spread in a canopy of 2–6 m (6 ft 7 in – 19 ft 8 in) in diameter. The shapes of the stems vary as some grow curved and there are multi-headed ones. The fronds are borne in flushes, with fertile and sterile fronds often in alternating layers. The largest individual at present for which there is photographic evidence is one at Weld Hill, Tasmania (ten miles (16 km) north-east of Craycroft) which has a trunk 39 feet (12 meters) in height, with a DBH (diameter at breast height) of four feet (1.2 meters) and is still three feet (0.9 meter) thick just beneath the rosette of 18 foot (5.5 meters) fronds. [1] [2]
The "trunk" of this fern is merely the decaying remains of earlier growth of the plant and forms a medium through which the roots grow. The trunk is usually solitary, without runners, but may produce offsets. They can be cut down and, if they are kept moist, the top portions can be replanted and will form new roots. The stump, however, will not regenerate since it is dead organic matter. In nature, the fibrous trunks are hosts for a range of epiphytic plants including other ferns and mosses.
The fern grows at 3.5 to 5 cm per year and produces spores at the age of about 20 years.
Reproduction by this species is primarily from spores, but it can also be grown from plantlets occurring around the base of the rhizome.
In cultivation, it can also be grown as a "cutting", a method not to be encouraged unless the tree-fern is doomed to die in its present position. This involves sawing the trunk through, usually at ground level, and removing the fronds; the top part will form roots and regrow, but the base will die.
The fern grows on damp, sheltered woodland slopes and moist gullies, and they occasionally occur at high altitudes in cloud forests. Dicksonia antarctica is the most abundant tree fern in South Eastern Australia.
The plant can grow in acid, neutral and alkaline soils. It can grow in semi-shade. It strongly resents drought or dryness at the roots, and does best in moist soil. Dicksonia antarctica is a long lived species in comparison to the trees that also grow in its natural habitat. While it does best in the dappled shade of other trees, it must also be able to survive high light intensities when a forest gap is created by the fall of a tree. It also shows adaptation to fire with the trunk and top of the plant being quite resistant to damage. [3]
Dicksonia antarctica grows best in areas of rainfall of over 1,000 mm per year but in lower rainfall areas does well in moist gullies. It is tolerant of fire and re-shoots readily after re-location. It can provide habitat for epiphytes and also provides shelter for more delicate fern species to flourish underneath.
Plant in organic soils and ensure the fern is kept mulched and watered. Dicksonia antarctica generally requires a minimum rainfall of 500 mm (20 inches) per year. In dry climates, a drip irrigation or spray system applied overhead is the most effective method of watering.
It is best to leave old fronds on the plant in order to protect the trunk from cold and desiccation. Winter protection of the trunk is recommended during prolonged or severe cold weather.
This plant is particularly suited to garden planting and landscaping purposes. As an ornamental plant, it is hardy to about −5 °C (23 °F), succeeding outdoors in the milder areas of Britain where it thrives and often self-sows in Cornish and Scottish west coast gardens. It has gained the Royal Horticultural Society's Award of Garden Merit. [4] [5]
Large Dicksonia antarctica available for sale come from old growth Tasmanian forests, and may be hundreds of years old. The trunks are also available legally from local suppliers who licence collection of minor species from Forestry Tasmania, the State Government GBE who manage forestry.
The soft tree fern can be used as a food source, with the pith of the plant being eaten either cooked or raw. It is a good source of starch. [6]
The 1889 book The Useful Native Plants of Australia records that "The pulp of the top of the trunk is full of starch, and is eaten by the aboriginals [sic.] both raw and roasted. The native blacks [sic.] of the colony used to split open about a foot and a-half of the top of the trunk, and take out the heart, in substance resembling a Swedish turnip, and of the thickness of a man's arm. This they either roasted in the ashes, or ate as bread; but it is too bitter and astringent to suit an English palate. (Gunn)" [7]
The tree ferns are arborescent (tree-like) ferns that grow with a trunk elevating the fronds above ground level, making them trees. Many extant tree ferns are members of the order Cyatheales, to which belong the families Cyatheaceae, Dicksoniaceae, Metaxyaceae, and Cibotiaceae. It is estimated that Cyatheales originated in the early Jurassic, and is the third group of ferns known to have given rise to tree-like forms. The others are the extinct Tempskya of uncertain position, and Osmundales where the extinct Guaireaceae and some members of Osmundaceae also grew into trees. In addition there were the Psaroniaceae including Tietea in the Marattiales, which is the sister group to most living ferns including Cyatheales.
The order Cyatheales, which includes most tree ferns, is a taxonomic order of the fern class, Polypodiopsida. No clear morphological features characterize all of the Cyatheales, but DNA sequence data indicate the order is monophyletic. Some species in the Cyatheales have tree-like growth forms from a vertical rhizome, others have shorter or horizontal expanding rhizomes.
A tropical garden is a type of garden that features tropical plants and requires heavy rainfall or a decent irrigation or sprinkler system for watering. These gardens typically need fertilizer and heavy mulching.
Sphaeropteris cooperi, synonym Cyathea cooperi, also known as lacy tree fern, scaly tree fern, or Cooper's tree fern, is a tree fern native to Australia, in New South Wales and Queensland.
Dicksonia squarrosa, the New Zealand tree fern, whekī or rough tree fern, is a common tree fern endemic to New Zealand. It has a slender black trunk that is usually surrounded by many dead brown fronds.
Sphaeropteris medullaris, synonym Cyathea medullaris, commonly known as mamaku or black tree fern, is a large tree fern up to 20 m tall. It is distributed across the south-west Pacific from Fiji to Pitcairn Island. Its other Māori names include katātā, kōrau, or pītau.
Sphaeropteris excelsa, synonym Cyathea brownii, commonly known as the Norfolk tree fern or smooth tree fern, is probably the largest fern species in the world. It is endemic to Norfolk Island, in the Pacific Ocean near Australia and New Zealand. It is named after the botanist Robert Brown (1773-1858).
Alsophila australis, synonym Cyathea australis, also known as the rough tree fern, is a species of tree fern native to southeastern Queensland, New South Wales and southern Victoria in Australia, as well as Tasmania and Norfolk Island.
Alsophila bryophila, synonym Cyathea bryophila, is a species of tree fern native to Puerto Rico, where it grows in the understory in wet montane and mossy forest at an altitude of 750–1200 m. The trunk is erect, up to 7 m tall and about 10 cm in diameter. Fronds are pinnate or bipinnate and grow to 2 m in length. The underside of the rachis is pubescent and has occasional scales towards the base. The scales range in colour from brown to bicoloured. Sori occur along each side of the pinnule midvein and are covered by scale-like indusia. A. bryophila is a slow growing species, reportedly only increasing in trunk height by 5 cm a year, a growth rate more akin to that of Dicksonia species. It has been estimated that plants may live in excess of 150 years.
Alsophila smithii, synonym Cyathea smithii, commonly known as the soft tree fern or kātote, is a species of tree fern from New Zealand.
Parablechnum wattsii, synonym Blechnum wattsii, is a common terrestrial fern growing in rainforest and open forest. It is often seen near creeks in much of south eastern Australia, including Victoria, Tasmania, South Australia, New South Wales and Queensland. The specific epithet wattsii honours William Walter Watts (1856-1920). Watts was considered an authority on mosses and ferns and has more than 30 species named for him. Common names by which the species may be called are hard water fern - from its stiff leathery fronds, leech fern - as forest workers often encounter leaches while working in clusters of these ferns, hard hill fern - from the fern's habit and habitat, and red cabbage fern - from the bronze-pink colour of the young fronds resembling cooked red cabbage.
Notogrammitis billardierei, also known as the common finger-fern, or common strap fern, is a small epiphytic or lithophytic fern [1] with small, strap like fronds, found commonly in wet forest in South-Eastern Australia and New Zealand.
Polystichum proliferum, commonly known as mother shield fern is an Australian endemic fern. The genus name Polystichum is derived from Greek poly - many, and stichos - rows referring to the many rows of sori. The species name is derived from Latin, Proli – offspring and fer - bearing referring to the proliferous buds, a prominent feature of the species.
Pteridium esculentum, commonly known as bracken fern, Austral bracken or simply bracken, is a species of the bracken genus native to a number of countries in the Southern Hemisphere. Esculentum means edible. First described as Pteris esculenta by German botanist Georg Forster in 1786, it gained its current binomial name in 1908. The Eora people of the Sydney region knew it as gurgi.
Pittosporum bicolor, commonly known as cheesewood or banyalla, is a flowering shrub or small tree of the family Pittosporaceae, and is native to south eastern Australia.
Dicksonia fibrosa, the golden tree fern, whekī-ponga, wheki-kōnga, or kurīpākā is a species of medium-sized tree fern native to New Zealand.
Adiantum venustum, the evergreen maidenhair or Himalayan maidenhair, is a species of fern in the genus Adiantum of the family Pteridaceae, native to China and the Himalayas. It is a slow to establish plant that usually grows on moist rocks and soil with a good amount of humus and dead leaves. It is very hardy, largely evergreen to -10 °C, when it becomes deciduous. It is also known as black Hansraj in India for its black stalks at the fronds.
Tasmania is home to 'Australia’s largest cool temperate rainforests. Most of Tasmania’s rainforests occur in the North-West and throughout the North East highlands. Cool temperate rainforests typically have a heavy rainfall, cool climate, favor high altitudes and have a limited availability of light.
Polyphlebium venosum, the veined bristle-fern or bristle filmy fern, is a fern in the family Hymenophyllaceae. It is only found in wet forests, mainly growing as an epiphyte on the shady side of the soft tree fern, Dicksonia antarctica. It also grows on logs, trunks of trees and rarely on trunks of Cyathea species or on wet rock-faces. It is found in the wetter parts of Eastern Australia and New Zealand. P. venosum has poor long-distance dispersal compared to other ferns due to its short lived spore. Notable features of Polyphlebium venosum include it being one cell layer thick, 5–15 cm in length, having many branching veins and a trumpet shaped indusium.
Tmesipteris obliqua, more commonly known as the long fork-fern or common fork-fern, is a weeping, epiphytic fern ally with narrow unbranched leafy stems. T. obliqua is a member of the genus Tmesipteris, commonly known as hanging fork-ferns. Tmesipteris is one of two genera in the order Psilotales, the other genus being Psilotum. T. obliqua is endemic to eastern Australia.