''Cercidiphyllum'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

containing two

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of plants, both commonly called katsura. They are the sole members of the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Cercidiphyllaceae. The genus is

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

to Japan and China and unrelated to ''

Cercis ''Cercis'' is a genus of about 10 species in the subfamily Cercidoideae of the pea family Fabaceae, native to warm temperate regions. It contains small deciduous trees or large shrubs commonly known as redbuds. They are characterised by simp ...

'' (redbuds).

Description

The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

, ''

Cercidiphyllum japonicum ''Cercidiphyllum japonicum'', known as the katsura (from its Japanese name カツラ, 桂), is a species of flowering tree in the family Cercidiphyllaceae native to China and Japan. It is sometimes called ''caramel tree'' for the light caramel sm ...

'', can reach in height, and is one of the largest hardwoods in Asia. The other species, ''

Cercidiphyllum magnificum ''Cercidiphyllum magnificum'', known as the large-leaf katsura or magnificent katsura tree, is a species of flowering tree in the family Cercidiphyllaceae native to Honshu, Japan. It is sometimes called caramel tree for the light, sweet smell it ...

'', is much smaller, rarely reaching over in height. ''Cercidiphyllum'' produces spurs along its twigs. These are short stems with closely spaced leaves. The

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

is dimorphic. According to a recent description "short shoots bear broadly

cordate Cordate is an adjective meaning ' heart-shaped' and is most typically used for: * Cordate (leaf shape) The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a ...

or reniform, palmately veined leaves with

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

margins; long shoots bear

elliptic In mathematics, an ellipse is a plane curve surrounding two focal points, such that for all points on the curve, the sum of the two distances to the focal points is a constant. It generalizes a circle, which is the special type of ellipse in ...

to broadly

ovate Ovate may refer to: * Ovate (egg-shaped) leaves, tepals, or other botanical parts *Ovate, a type of prehistoric stone hand axe *Ovates, one of three ranks of membership in the Welsh Gorsedd *Vates In modern English, the nouns vates () and ova ...

leaves with

entire Entire may refer to: * Entire function, a function that is holomorphic on the whole complex plane * Entire (animal), an indication that an animal is not neutered * Entire (botany) This glossary of botanical terms is a list of definitions of ...

or finely

serrate Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied p ...

margins."Peter K. Endress. 1993. "Cercidiphyllaceae" pages 250-252. In: Klaus Kubitzki (editor). ''The Families and Genera of Vascular Plants''. volume II. Springer-Verlag: Berlin; Heidelberg, Germany. Leaf size varies from 3–8 cm long and 3–5.5 cm broad. The genus is dioecious, having separate male and female trees. The small inconspicuous

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s are produced in early spring and wind-pollinated; the

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a cluster of 2-4 small pods, each pod 1–2 cm long with numerous small, flattened and winged

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s. The fruits mature in autumn and release their seeds in autumn through winter. The leaves have a strong, sweet smell in the fall, described as caramel or

Madeira cake Madeira cake is a sponge or butter cake in traditional British and Irish cookery. Origin It is sometimes mistakenly thought to originate from the Madeira Islands; however, that is not the case as it was named after Madeira wine, a Portuguese wi ...

-like. The smell comes from a combination of

maltol Maltol is a naturally occurring organic compound that is used primarily as a flavor enhancer. It is found in the bark of larch tree, in pine needles, and in roasted malt (from which it gets its name). It is a white crystalline powder that is ...

and a sugary compound in the leaves and is strongest when they are brown. In German, ''Cercidiphyllum'' trees are named after their scent; or ("pie tree" or "gingerbread tree").

Nomenclature

Katsura () is the

Japanese Japanese may refer to: * Something from or related to Japan, an island country in East Asia * Japanese language, spoken mainly in Japan * Japanese people, the ethnic group that identifies with Japan through ancestry or culture ** Japanese diaspor ...

name for the tree. The scientific name ''Cercidiphyllum'' refers to the close resemblance of the leaves to those of ''

'' (redbuds); these two unrelated genera can however be distinguished easily as redbud leaves are alternate, not opposite.

Species

The two species are: *''

''. Throughout the range of the genus. Typically a multi-stemmed tree to 40–45 m tall in the wild, though typically smaller in cultivation. Bark rough, furrowed. Leaves smaller, not over 4.5 cm long and 3.2 cm broad;

stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

s falling soon after leafing out in spring. Seed winged only at lower end. Plants from China were at one time separated as ''C. japonicum'' var. ''sinense'', but no consistent difference between Japanese and Chinese origins has been found. *''

''.

Endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to central Honshū, where it grows at higher altitudes than ''C. japonicum''. A small tree, not more than 10 m tall. Bark smooth. Leaves larger, up to 8 cm long and 5.5 cm broad; stipules persistent. Seed winged at both ends.

Cultivation

Katsura is grown as an ornamental tree for its delicate heart-shaped leaves and bright autumn colour, a mix of bright yellow, pink and orange-red. Where conditions are suitable, it is fast-growing, but it is very sensitive to

drought A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...

and needs deep, permanently moist soil. Under drought conditions, the species will abscise its leaves; however refoliation may occur once water is made available. Of particular interest is the scent produced by the leaves in the autumn, resembling burnt brown sugar or cotton candy. Trees in cultivation, like those in natural environments, tend to sucker from the base when young and become multi-stemmed at maturity; pruning to maintain a single stem is not advised. Within ''Cercidiphyllum japonicum'', several

cultivar A cultivar is a type of cultivated plant that people have selected for desired traits and when propagated retain those traits. Methods used to propagate cultivars include: division, root and stem cuttings, offsets, grafting, tissue culture ...

s with pendulous branches are grown for their unique weeping habit. Two general types exist. Those with a strong central leader, or excurrent growth, are all one clone originating in Morioka City, Japan. This cultivar is known as 'Morioka Weeping' and can reach over in height. The other type fails to form a central leader and is rounded in habit. There are several clones of this, including 'Amazing Grace' and 'Tidal Wave'. Both the species ''C. japonicum'' and the weeping form ''C. japonicum'' f. ''pendulum'' have gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr (Nor ...

's Award of Garden Merit.

Uses

Katsura wood is often used to make gobans, i.e.

boards Board or Boards may refer to: Flat surface * Lumber, or other rigid material, milled or sawn flat ** Plank (wood) ** Cutting board ** Sounding board, of a musical instrument * Cardboard (paper product) * Paperboard * Fiberboard ** Hardboard, a t ...

for the game Go.

Fossil record

The genus is known from fossils at the end of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

(

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval ...

) of North America, and the Cenozoic of North America, Europe and Asia.

Gallery

File:Katsura Tree Cercidiphyllum japonicum Trunk Bark 2000px.jpg, ''Cercidiphyllum japonicum'' Trunk bark File:Cercidiphyllum japonicum JPG01b.jpg, ''Cercidiphyllum japonicum'' leaves File:Great katsura of wachi01s3000.jpg, "great Katsura of Wachi" File:Cercidiphyllum japonicum JPG01d.jpg, ''Cercidiphyllum japonicum'' in the autumn

References

Sources

* * * *

External links

''Cercidiphyllum'' images at the Arnold Arboretum of Harvard University Plant Image Database
* Dosman, Michael
"The Katsure Collection."
''Arnold Arboretum of Harvard University website'', Fall 2012. Accessed 1 May 2020. {{Go (game) Dioecious plants Go equipment Japanese woods Saxifragales Saxifragales genera Extant Late Cretaceous first appearances