A clonal colony or genet is a group of genetics identical individuals, such as , 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 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, reproduction occurs by underground or in some plants. Above ground, these plants most often 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
, clonal colonies arise by wide-ranging
that at intervals send up new shoots, termed
basal shoot.
and
with
that may tend to bend and rest on the ground, or which possess the ability to form
can form colonies via layering, or aerial rooting, e.g.
willow,
blackberry,
Ficus, and
banyan. Some
naturally form
adventitious roots on their
plant stem that take root in the soil when the stems contact the ground, e.g.
Hedera and
trumpet vine. With other vines, rooting of the stem where nodes come into contact with soil may establish a clonal colony, e.g.
Wisteria.
and many
herbaceous often form clonal colonies via horizontal underground stems termed
, e.g. ostrich fern
Matteuccia struthiopteris and
goldenrod. A number of herbaceous flowering plants form clonal colonies via horizontal surface stems termed
, or runners; e.g.
strawberry and many
. Non-woody plants with underground
such as
and
can also form colonies, e.g.
Narcissus and
Crocus. A few plant species can form colonies via adventitious
that form on leaves, e.g.
Kalanchoe daigremontiana and
Tolmiea menziesii. A few plant species can form colonies via asexual seeds, termed
apomixis, e.g.
dandelion.
Record colonies
The only known natural example of King's Lomatia (
Lomatia tasmanica) found growing in the wild is a clonal colony in
Tasmania estimated to be 43,600 years old.
A group of 47,000 Quaking Aspen ( Populus tremuloides) trees (nicknamed "Pando") in the Wasatch Mountains, Utah, United States, has been shown to be a single clone connected by the root system. It is sometimes considered the world's largest organism by mass, covering , and also as among the world's oldest living organisms, at an estimated 14,000 years old.
Another possible candidate for oldest organism on earth is an underwater meadow of the marine botany Posidonia oceanica in the Mediterranean Sea, 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
plant nutrition. A few non-vining, woody plants that form clonal colonies are
Bigelow oak (
Quercus sinuata var.
breviloba),
(
Populus tremuloides),
bayberry (
Myrica pensylvanica),
black locust (
Robinia pseudoacacia),
creosote bush (
Larrea tridentata),
Staphylea,
blueberry (
Vaccinium), devil's club (
Oplopanax horridus),
forsythia,
hazelnut (
Corylus),
honey locust (
Gleditsia triacanthos), Kentucky coffeetree (
Gymnocladus dioicus), kerria (
Kerria japonica),
Asimina triloba (
Asimina triloba),
Populus (
Populus),
sassafras (
Sassafras albidum),
sumac (
Rhus), sweetgum (
Liquidambar styraciflua), and
sweetshrub (
Calycanthus floridus).
See also
Further reading
-
Kricher, J. C., & Morrison, G. (1988). A Field Guide to Eastern Forests, pp. 19–20. Peterson Field Guide Series. .
