''Taxodium'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of one to three

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

(depending on

taxonomic 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme of classes (a taxonomy) and the allocation ...

opinion) of extremely

flood A flood is an overflow of water (list of non-water floods, or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant con ...

-tolerant

conifer Conifers () are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a sin ...

s in the cypress family,

Cupressaceae Cupressaceae or the cypress family is a family of conifers. The family includes 27–30 genera (17 monotypic), which include the junipers and redwoods, with about 130–140 species in total. They are monoecious, subdioecious or (rarely) dioecio ...

. The name is derived from the

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

word ''taxus'', meaning "

yew Yew is a common name given to various species of trees. It is most prominently given to any of various coniferous trees and shrubs in the genus '' Taxus'': * European yew or common yew (''Taxus baccata'') * Pacific yew or western yew ('' Taxus ...

", and the

Greek Greek may refer to: Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of all kno ...

word ''εἶδος'' (''eidos''), meaning "similar to." Within the family, ''Taxodium'' is most closely related to Chinese swamp cypress (''Glyptostrobus pensilis'') and

sugi ''Cryptomeria'' (literally "hidden parts") is a monotypic genus of conifer in the cypress family Cupressaceae. It includes only one species, ''Cryptomeria japonica'' ( syn. ''Cupressus japonica'' L.f.). It is considered to be endemic to Japan ...

(''Cryptomeria japonica''). Species of ''Taxodium'' occur in the southern part of the

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

n continent and are

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

in the north and semi-evergreen to

evergreen In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...

in the south. They are large

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

s, reaching tall and (exceptionally ) trunk diameter. The needle-like

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

, long, are borne spirally on the

shoot Shoot most commonly refers to: * Shoot (botany), an immature plant or portion of a plant * Shooting, the firing of projectile weapons * Photo shoot, a photography session; an event wherein a photographer takes photographs Shoot may also refer t ...

s, twisted at the base so as to appear in two flat rows on either side of the shoot. The

cones In geometry, a cone is a three-dimensional figure that tapers smoothly from a flat base (typically a circle) to a point not contained in the base, called the ''apex'' or '' vertex''. A cone is formed by a set of line segments, half-lines, ...

are globose, diameter, with 10–25 scales, each scale with one or two

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s; they are mature in 7–9 months after

pollination Pollination is the transfer of pollen from an anther of a plant to the stigma (botany), stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example bees, beetles or bu ...

, when they disintegrate to release the seeds. The male (

pollen Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...

) cones are produced in pendulous

raceme A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...

s, and shed their pollen in early spring. ''Taxodium'' species grow

cypress knees A cypress knee is a distinctive structure forming above the roots of a Cupressaceae, cypress tree of any of various species of the subfamily Cupressaceae#Classification, Taxodioideae, such as the Taxodium distichum, bald cypress. Their function ...

, when growing in or beside water. The function of these knees is currently a subject of ongoing research.

Species

The three extant

taxa In biology, a taxon (back-formation from ''taxonomy''; : 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 name and ...

of ''Taxodium'' are treated here as distinct species, though some

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

s treat them in just one or two species, with the others considered as varieties of the first described. The three are distinct in

ecology Ecology () is the natural science of the relationships among living organisms and their Natural environment, environment. Ecology considers organisms at the individual, population, community (ecology), community, ecosystem, and biosphere lev ...

, growing in different environments, but hybridise where they meet. *†''

Taxodium dubium ''Taxodium dubium'' is an extinct species of cypress in the genus ''Taxodium'' in the family Cupressaceae which lived from the Late Paleocene to the Pliocene in North America and Europe. The species was first described in 1823 by Kaspar Maria v ...

'' (Sternb.) Heer

Formerly placed here

* ''

Glyptostrobus pensilis ''Glyptostrobus pensilis'', known in Chinese as 水松 (Shuǐ sōng), and also Chinese swamp cypress, is an endangered conifer, and the sole living species in the genus ''Glyptostrobus''. Description It is a medium-sized to large tree, rea ...

'' (Staunton ex D.Don) K.Koch (as ''T. japonicum'' var. ''heterophyllum'' Brongn.) * ''

Sequoia sempervirens ''Sequoia sempervirens'' ()''Sunset Western Garden Book,'' 1995: 606–607 is the sole living species of the genus ''Sequoia (genus), Sequoia'' in the cypress family Cupressaceae (formerly treated in Taxodiaceae). Common names include coast ...

'' (D.Don) Endl. (as ''T. sempervirens'' D.Don)

Uses

The trees are especially prized for their

wood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

, of which the

heartwood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

is extremely rot- and

termite Termites are a group of detritivore, detritophagous Eusociality, eusocial cockroaches which consume a variety of Detritus, decaying plant material, generally in the form of wood, Plant litter, leaf litter, and Humus, soil humus. They are dist ...

-resistant. The heartwood contains a

sesquiterpene Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many combinations. Biochemical modifications s ...

called cypressene, which acts as a natural

preservative A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or ...

. It takes decades for cypressene to accumulate in the wood, so lumber taken from old-growth trees is more rot resistant than that from second-growth trees. However, age also increases susceptibility to Pecky Rot fungus (''

Stereum ''Stereum'' is the type genus of the Stereaceae family of fungi, in the Russulales order. Common names for species of this genus include leaf fungus, wax fungus, and shelf fungus. Fungi having a shape similar to a ''Stereum'' are said to have a s ...

taxodii''), which attacks the heartwood and causes some damaged trees to become hollow and thus useless for timber. Bald Cypress wood was much used in former days in the southeastern United States for

roof shingle A roof’s shingles are a roof covering consisting of individual overlapping elements. These elements are typically flat, rectangular shapes laid in courses from the bottom edge of the roof up, with each successive course overlapping the joint ...

s. The shredded

bark Bark may refer to: Common meanings * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Arts and entertainment * ''Bark'' (Jefferson Airplane album), ...

of these trees is used as a

mulch A mulch is a layer of material applied to the surface of soil. Reasons for applying mulch include conservation of soil moisture, improving soil fertility, fertility and health of the soil, reducing Weed control, weed growth, and enhancing the v ...

Evolution

Fossil-leaf Taxodium dubium Tertiary Germany

In earth's history ''Taxodium'' was much more widespread in the Northern Hemisphere than today. The oldest fossils were found in

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

deposits from North America. The trees persisted in Europe until around 2.5 million years ago, during the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Bükkábrány mummified forest

References

External links

Gymnosperm Database - TaxodiumCorkscrew Swamp Sanctuary website
*National Audubon Society, undated. ''Corkscrew Swamp Sanctuary. A Companion Field Guide''. Artype Inc., Ft. Myers. 25 p. {{Authority control Extant Late Cretaceous first appearances Conifer genera Deciduous conifers