Dicranopteris linearis
Encyclopedia
Dicranopteris linearis is a common species of fern
known by many common names, including Old World forked fern and uluhe (Hawaiian
). It is one of the most widely distributed ferns of the wet Old World
tropics and adjacent regions, including Polynesia
and the Pacific
. In parts of the New World
tropics its niche
is filled by its relative, Dicranopteris pectinatus.
This rhizomatous
fern spreads via cloning
, spreading along the ground and climbing on other vegetation, often forming thickets 3 meters deep or more. The stem grows from the rhizome, branches at a 45° angle, and forms fronds that continue to bud and branch. In this way the growth can continue for a long distance as the plant forms a mat, grows over itself in layers, and spreads. When climbing, the leafy branches can reach over 6 meters longand can climb 10 high when supported by a tree. The ultimate segments of the leaves are linear in shape, up to 7 centimeters long by a few millimeters wide. The undersides are hairy and sometimes waxy. It can also reproduce via spores.
The fern grows easily on poorly drained, nutrient-poor soils and in disturbed habitat and steep slopes. It does not tolerate shade
, so once established it will eventually be shaded out by taller vegetation unless it climbs above it. It may suppress the growth of new stands of trees, especially when it becomes a dense thicket.
The fern is a keystone species
in Hawaiian ecosystems, and dominates
many areas in Hawaiian rainforests. It occurs on all the main Hawaiian islands. As a pioneer species
in ecological succession
, it can colonize bare sites such as lava flows, talus
, and abandoned roads. When the fern grows onto a new site it produces layers of stems and leaves repeatedly until there is a network of vegetation. The leaves die and the stems are very slow to decompose, so the network persists. The network then fills with organic forest detritus, forming a litter layer which can be a meter thick. The network is penetrated by the fern's rhizomes and roots, such that the fern serves as its own substrate. Where the fern is eliminated, invasive species
of plants can move in, so "one important function" of the fern is to prevent these plants from encroaching on the rainforest. The fern may have allelopathic
effects, preventing the growth of other plants. Also, the fern is a very productive member of the forest ecosystem; despite being a relatively small amount of the biomass
in the forest it accounts for over half of the primary productivity
in some areas.
This plant is used medicinally to treat intestinal worms in Indochina
, skin ulcers and wounds in New Guinea
, and fever in Malaysia. In vitro samples of the fern kill bacteria
.
The fiddlehead
s of the fern are used in floral arrangements.
Fern
A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...
known by many common names, including Old World forked fern and uluhe (Hawaiian
Hawaiian language
The Hawaiian language is a Polynesian language that takes its name from Hawaii, the largest island in the tropical North Pacific archipelago where it developed. Hawaiian, along with English, is an official language of the state of Hawaii...
). It is one of the most widely distributed ferns of the wet Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
tropics and adjacent regions, including Polynesia
Polynesia
Polynesia is a subregion of Oceania, made up of over 1,000 islands scattered over the central and southern Pacific Ocean. The indigenous people who inhabit the islands of Polynesia are termed Polynesians and they share many similar traits including language, culture and beliefs...
and the Pacific
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
. In parts of the New World
New World
The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...
tropics its niche
Ecological niche
In ecology, a niche is a term describing the relational position of a species or population in its ecosystem to each other; e.g. a dolphin could potentially be in another ecological niche from one that travels in a different pod if the members of these pods utilize significantly different food...
is filled by its relative, Dicranopteris pectinatus.
This rhizomatous
Rhizome
In botany and dendrology, a rhizome is a characteristically horizontal stem of a plant that is usually found underground, often sending out roots and shoots from its nodes...
fern spreads via cloning
Cloning
Cloning in biology is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments , cells , or...
, spreading along the ground and climbing on other vegetation, often forming thickets 3 meters deep or more. The stem grows from the rhizome, branches at a 45° angle, and forms fronds that continue to bud and branch. In this way the growth can continue for a long distance as the plant forms a mat, grows over itself in layers, and spreads. When climbing, the leafy branches can reach over 6 meters longand can climb 10 high when supported by a tree. The ultimate segments of the leaves are linear in shape, up to 7 centimeters long by a few millimeters wide. The undersides are hairy and sometimes waxy. It can also reproduce via spores.
The fern grows easily on poorly drained, nutrient-poor soils and in disturbed habitat and steep slopes. It does not tolerate shade
Shade
Shade is the blocking of sunlight by any object, and also the shadow created by that object. Shade also consists of the colors grey, black, white, etc...
, so once established it will eventually be shaded out by taller vegetation unless it climbs above it. It may suppress the growth of new stands of trees, especially when it becomes a dense thicket.
The fern is a keystone species
Keystone species
A keystone species is a species that has a disproportionately large effect on its environment relative to its abundance. Such species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and...
in Hawaiian ecosystems, and dominates
Dominant species
Dominant species may mean:*Dominant species , one of a small number of species which dominate in an ecological community*Dominant Species by Michael E. Marks*Dominant Species...
many areas in Hawaiian rainforests. It occurs on all the main Hawaiian islands. As a pioneer species
Pioneer species
Pioneer species are species which colonize previously uncolonized land, usually leading to ecological succession. They are the first organisms to start the chain of events leading to a livable biosphere or ecosystem...
in ecological succession
Ecological succession
Ecological succession, is the phenomenon or process by which a community progressively transforms itself until a stable community is formed. It is a fundamental concept in ecology, and refers to more or less predictable and orderly changes in the composition or structure of an ecological community...
, it can colonize bare sites such as lava flows, talus
Scree
Scree, also called talus, is a term given to an accumulation of broken rock fragments at the base of crags, mountain cliffs, or valley shoulders. Landforms associated with these materials are sometimes called scree slopes or talus piles...
, and abandoned roads. When the fern grows onto a new site it produces layers of stems and leaves repeatedly until there is a network of vegetation. The leaves die and the stems are very slow to decompose, so the network persists. The network then fills with organic forest detritus, forming a litter layer which can be a meter thick. The network is penetrated by the fern's rhizomes and roots, such that the fern serves as its own substrate. Where the fern is eliminated, invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
of plants can move in, so "one important function" of the fern is to prevent these plants from encroaching on the rainforest. The fern may have allelopathic
Allelopathy
Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the growth, survival, and reproduction of other organisms. These biochemicals are known as allelochemicals and can have beneficial or detrimental effects on the target organisms...
effects, preventing the growth of other plants. Also, the fern is a very productive member of the forest ecosystem; despite being a relatively small amount of the biomass
Biomass
Biomass, as a renewable energy source, is biological material from living, or recently living organisms. As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel....
in the forest it accounts for over half of the primary productivity
Primary production
400px|thumb|Global oceanic and terrestrial photoautotroph abundance, from September [[1997]] to August 2000. As an estimate of autotroph biomass, it is only a rough indicator of primary production potential, and not an actual estimate of it...
in some areas.
This plant is used medicinally to treat intestinal worms in Indochina
Indochina
The Indochinese peninsula, is a region in Southeast Asia. It lies roughly southwest of China, and east of India. The name has its origins in the French, Indochine, as a combination of the names of "China" and "India", and was adopted when French colonizers in Vietnam began expanding their territory...
, skin ulcers and wounds in New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, and fever in Malaysia. In vitro samples of the fern kill bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
.
The fiddlehead
Fiddlehead
Fiddleheads or Fiddlehead greens are the furled fronds of a young fern, harvested for use as a vegetable. Left on the plant, each fiddlehead would unroll into a new frond...
s of the fern are used in floral arrangements.