Clonal colony
Encyclopedia
A clonal colony
or genet is a group of genetically identical individuals (e. g., plant
s, fungi, or bacteria
) that have grown in a given location, all originating vegetatively
(not sexually) from a single ancestor. In plants, an individual in such a population is referred to as a ramet. In fungi, "individuals" typically refers to the visible fruiting bodies or mushroom
s that develop from a common mycelium
which, although spread over a large area, is otherwise hidden in the soil. Clonal colonies are common in many plant species. Although many plants reproduce sexually through the production of seed, some plants reproduce by underground stolons or rhizomes. Above ground these plants appear to be distinct individuals, but underground they remain interconnected and are all clones of the same plant. However, it is not always easy to recognize a clonal colony especially if it spreads underground and is also sexually reproducing.
") in the Wasatch Mountains, Utah
, USA, is sometimes considered the world's largest organism by mass, covering 43 hectares (106.3 acre). It is possible that other unknown clonal colonies of trees rival or exceed its size.
The only known plant of King's Lomatia
(Lomatia tasmanica) in Tasmania
is a clonal colony estimated to be 43,600 years old. Another possible candidate for oldest organism on earth is a stand of the marine plant Posidonia oceanica
in the Mediterranean Sea
, which could be up to 100,000 years of age.
. A few non-vining woody plants that form clonal colonies are:
Colony (biology)
In biology, a colony reference to several individual organisms of the same species living closely together, usually for mutual benefit, such as stronger defense or the ability to attack bigger prey. Some insects live only in colonies...
or genet is a group of genetically identical individuals (e. g., plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s, fungi, or 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...
) that have grown in a given location, all originating vegetatively
Vegetative reproduction
Vegetative reproduction is a form of asexual reproduction in plants. It is a process by which new individuals arise without production of seeds or spores...
(not sexually) from a single ancestor. In plants, an individual in such a population is referred to as a ramet. In fungi, "individuals" typically refers to the visible fruiting bodies or mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...
s that develop from a common mycelium
Mycelium
thumb|right|Fungal myceliaMycelium is the vegetative part of a fungus, consisting of a mass of branching, thread-like hyphae. The mass of hyphae is sometimes called shiro, especially within the fairy ring fungi. Fungal colonies composed of mycelia are found in soil and on or within many other...
which, although spread over a large area, is otherwise hidden in the soil. Clonal colonies are common in many plant species. Although many plants reproduce sexually through the production of seed, some plants reproduce by underground stolons or rhizomes. Above ground these plants appear to be distinct individuals, but underground they remain interconnected and are all clones of the same plant. However, it is not always easy to recognize a clonal colony especially if it spreads underground and is also sexually reproducing.
Methods of establishment
- With most woody plants, clonal colonies arise by wide-ranging roots that at intervals send up new shoots, termed suckersBasal shootA basal shoot, root sprout, adventitious shoot, water sprout or sucker is a shoot or cane which grows from a bud at the base of a tree or shrub or from its roots. This shoot then becomes, or takes the form of, a singular plant. A plant that produces suckers is referred to as surculose...
. - Trees and shrubs with branches that touch the ground can form colonies via layeringLayeringLayering is a means of plant propagation in which a portion of an aerial stem grows roots while still attached to the parent plant and then detaches as an independent plant. Layering has evolved as a common means of vegetative propagation of numerous species in natural environments...
, e. g. willowWillowWillows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...
and blackberryBlackberryThe blackberry is an edible fruit produced by any of several species in the Rubus genus of the Rosaceae family. The fruit is not a true berry; botanically it is termed an aggregate fruit, composed of small drupelets. The plants typically have biennial canes and perennial roots. Blackberries and...
. - Some vines naturally form adventitiousAdventitiousAdventitious has various meanings in various disciplines and in general usage.Adventitious is from the Latin root advenire, meaning "to come or be superadded" and in correct English the meanings tend to have connections to accidental or casual occurrence...
roots on their stemPlant stemA stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...
s that take root in the soil when the stems contact the ground, e. g. ivy and trumpet vineTrumpet vineThe trumpet vine or trumpet creeper , also known as "cow itch vine" and as "hummingbird vine", is a large and vigorous woody vine of the family Bignoniaceae, notable for its showy trumpet-shaped flowers...
. - With other vines, rooting of the stem where nodes come into contact with soil may establish a clonal colony, e. g. WisteriaWisteriaWisteria is a genus of flowering plants in the pea family, Fabaceae, that includes ten species of woody climbing vines native to the eastern United States and to China, Korea, and Japan. Aquarists refer to the species Hygrophila difformis, in the family Acanthaceae, as Water Wisteria...
. - Ferns and many herbaceous flowering plants often form clonal colonies via horizontal underground stems termed rhizomeRhizomeIn 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...
s, e.g. ostrich fern Matteuccia struthiopteris and goldenrodGoldenrodSolidago, commonly called goldenrods, is a genus of about 100 species of flowering plants in the family Asteraceae. Most are herbaceous perennial species found in the meadows and pastures, along roads, ditches and waste areas in North America. There are also a few species native to Mexico, South...
. - A number of herbaceous flowering plants form clonal colonies via horizontal surface stems termed stolonStolonIn biology, stolons are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external skeletons.-In botany:...
s, or runners; e.g.strawberryStrawberryFragaria is a genus of flowering plants in the rose family, Rosaceae, commonly known as strawberries for their edible fruits. Although it is commonly thought that strawberries get their name from straw being used as a mulch in cultivating the plants, the etymology of the word is uncertain. There...
and many grassGrassGrasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
es. - Nonwoody plants with underground storage organStorage organA storage organ is a part of a plant specifically modified for storage of energy or water. Storage organs often grow underground, where they are better protected from attack by herbivores. Plants that have an underground storage organ are called geophytes in the Raunkiær plant life-form...
s such as bulbBulbA bulb is a short stem with fleshy leaves or leaf bases. The leaves often function as food storage organs during dormancy.A bulb's leaf bases, known as scales, generally do not support leaves, but contain food reserves to enable the plant to survive adverse conditions. At the center of the bulb is...
s and cormCormA corm is a short, vertical, swollen underground plant stem that serves as a storage organ used by some plants to survive winter or other adverse conditions such as summer drought and heat ....
s can also form colonies, e. g. Narcissus and CrocusCrocusCrocus is a genus in the iris family comprising about 80 species of perennials growing from corms. Many are cultivated for their flowers appearing in autumn, winter, or spring...
. - A few plant species can form colonies via adventitious plantlets that form on leaves, e. g. Kalanchoe daigremontianaKalanchoe daigremontianaKalanchoe daigremontiana syn. Bryophyllum daigremontianum also called Devil's Backbone, Alligator Plant, Mexican Hat Plant or Mother of Thousands is a succulent plant native to Madagascar. This plant is distinguished by its ability to propagate via vegetative propagation...
and Tolmiea menziesii. - A few plant species can form colonies via asexual seeds, termed apomixisApomixisIn botany, apomixis was defined by Winkler as replacement of the normal sexual reproduction by asexual reproduction, without fertilization. This definition notably does not mention meiosis...
, e. g. dandelion.
Record colonies
A group of 47,000 Quaking Aspen (Populus tremuloides) clones (nicknamed "PandoPando (tree)
Pando is a clonal colony of a single male Quaking Aspen located in the U.S. state of Utah, all determined to be part of a single living organism by identical genetic markers and one massive underground root system, although whether it is a single tree is disputed...
") in the Wasatch Mountains, Utah
Utah
Utah is a state in the Western United States. It was the 45th state to join the Union, on January 4, 1896. Approximately 80% of Utah's 2,763,885 people live along the Wasatch Front, centering on Salt Lake City. This leaves vast expanses of the state nearly uninhabited, making the population the...
, USA, is sometimes considered the world's largest organism by mass, covering 43 hectares (106.3 acre). It is possible that other unknown clonal colonies of trees rival or exceed its size.
The only known plant of King's Lomatia
King's Lomatia
King's Lomatia is a Tasmanian shrub from the family Proteaceae. The plant has shiny green leaves and bears pink flowers, but yields neither fruit nor seeds. Only one colony of King's Lomatia is known to be alive in the wild...
(Lomatia tasmanica) in Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
is a clonal colony estimated to be 43,600 years old. Another possible candidate for oldest organism on earth is a stand of the marine plant Posidonia oceanica
Posidonia oceanica
Posidonia oceanica is a seagrass species that is endemic to the Mediterranean Sea. It forms large underwater meadows that are an important part of the ecosystem. The fruit is free floating and known in Italy as 'the olive of the sea'...
in the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
, which could be up to 100,000 years of age.
Examples
When woody plants form clonal colonies, they often remain connected through the root system, sharing roots, water and mineral nutrientsPlant nutrition
'Plant Nutrition is the study of the chemical elements that are necessary for growth. In 1972, E. Epstein defined 2 criteria for an element to be essential for plant growth:# in its absence the plant is unable to complete a normal life cycle or...
. A few non-vining woody plants that form clonal colonies are:
- Bayberry, Myrica pensylvanica
- Black locustBlack locustRobinia pseudoacacia, commonly known as the Black Locust, is a tree in the subfamily Faboideae of the pea family Fabaceae. It is native to the southeastern United States, but has been widely planted and naturalized elsewhere in temperate North America, Europe, Southern Africa and Asia and is...
, Robinia pseudoacacia - BladdernutBladdernutStaphylea is a small genus of 10 or 11 species of flowering plants in the family Staphyleaceae, native to temperate regions of the Northern Hemisphere. The highest species diversity is in China, where four species occur....
, Staphylea species - BlueberryBlueberryBlueberries are flowering plants of the genus Vaccinium with dark-blue berries and are perennial...
, Vaccinium species - Devil's ClubDevil's ClubDevil's Club is a large shrub primarily native to the cool moist forests of western North America, but also disjunct on islands in Lake Superior. It is noted for its large palmate leaves and erect, woody stems covered in brittle spines...
Oplopanax horridus - ForsythiaForsythiaForsythia is a genus of flowering plants in the family Oleaceae . There are about 11 species, mostly native to eastern Asia, but one native to southeastern Europe. The common name is also Forsythia; the genus is named after William Forsyth.-Growth:They are deciduous shrubs typically growing to a...
, Forsythia species - HazelnutHazelnutA hazelnut is the nut of the hazel and is also known as a cob nut or filbert nut according to species. A cob is roughly spherical to oval, about 15–25 mm long and 10–15 mm in diameter, with an outer fibrous husk surrounding a smooth shell. A filbert is more elongated, being about twice...
, Corylus species - Honey locustHoney locustThe Honey locust, Gleditsia triacanthos, is a deciduous tree native to central North America. It is mostly found in the moist soil of river valleys ranging from southeastern South Dakota to New Orleans and central Texas, and as far east as eastern Massachusetts.-Description:Honey locusts, Gleditsia...
, Gleditsia triacanthos - Kentucky coffeetreeKentucky coffeetreeThe Kentucky Coffeetree, Gymnocladus dioicus, is a tree in the subfamily Caesalpinioideae of the pea family Fabaceae, native to the midwest of North America.-Introduction:...
, Gymnocladus dioicus - Kerria, Kerria japonica
- PawpawAsimina trilobaAsimina triloba, the pawpaw, paw paw, paw-paw, or common pawpaw, is a species of Asimina in the same plant family as the custard-apple, cherimoya, sweetsop, ylang-ylang and soursop...
, Asimina triloba - Pando treePando (tree)Pando is a clonal colony of a single male Quaking Aspen located in the U.S. state of Utah, all determined to be part of a single living organism by identical genetic markers and one massive underground root system, although whether it is a single tree is disputed...
, a clonal colony of a single male Populus tremuloides, all determined to be part of a single living organism - PoplarPoplarPopulus is a genus of 25–35 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar , aspen, and cottonwood....
s, Populus species - SassafrasSassafrasSassafras is a genus of three extant and one extinct species of deciduous trees in the family Lauraceae, native to eastern North America and eastern Asia.-Overview:...
, Sassafras albidum - SumacSumacSumac is any one of approximately 250 species of flowering plants in the genus Rhus and related genera, in the family Anacardiaceae. Sumacs grow in subtropical and temperate regions throughout the world, especially in Africa and North America....
, Rhus species - Sweetgum, Liquidambar styraciflua
- Sweetshrub, Calycanthus floridus
Further reading
- Kricher, J. C., & Morrison, G. (1988). A Field Guide to Eastern Forests, pp. 19-20. Peterson Field Guide Series. ISBN 0-395-35346-7.