''Cercidiphyllum japonicum'', known as the katsura (from its Japanese name カツラ, 桂), is a species of flowering tree in the family

Cercidiphyllaceae ''Cercidiphyllum'' is a genus containing two species of plants, both commonly called katsura. They are the sole members of the monotypic family Cercidiphyllaceae. The genus is native to Japan and China and unrelated to ''Cercis'' (redbuds). D ...

native to

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...

and

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

. It is sometimes called ''caramel tree'' for the light

caramel Caramel ( or ) is an orange-brown confectionery product made by heating a range of sugars. It can be used as a flavoring in puddings and desserts, as a filling in bonbons, or as a topping for ice cream and custard. The process of carameli ...

smell it emits during leaf fall.

Description

The tree is

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 leaves, usually in the autumn; to the shedding of petals, ...

and grows to 10–45 meters tall, with a trunk diameter of up to 2 meters (rarely more).Andrews, S. (1998, 1999). Tree of the Year: ''Cercidiphyllum japonicum''. ''International Dendrology Society Yearbook'' 1997: 17-45; 1998: 33-38.Flora of China
''Cercidiphyllum japonicum''
/ref>Chen, C., Liu, Y-H., Fu, C-X., & Qiu, Y-X. (2010). New microsatellite markers for the rare plant ''Cercidiphyllum japonicum'' and their utility for ''Cercidiphyllum magnificum''. ''Amer. J. Bot''. 97 (9): e82–e8
full text
Cercidiphyllum japonicum JPG01b

The shoots are dimorphic, with long shoots forming the structure of the branches and short shoots being born from their second year onward. The leaves are produced in opposite pairs on long shoots and singly on short shoots; they have a 1.4–4.7 cm petiole, and are rounded with a heart-shaped base and a crenate margin. Leaves on short shoots are larger, 3.7–9 cm long and 5–8.3 cm broad, and those on long shoots smaller, being 3.2–4.5 cm long and 1.9–3.2 cm broad. The leaves turn a variety of pinks and yellows in autumn and sometimes have a distinctive

scent when in fresh autumn colors. The flowers are inconspicuous and produced in early spring among the opening leaves, with male and female flowers on separate plants (

dioecious Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproducti ...

). The fruit is a cluster of two to four follicles 1–1.8 cm long and 2–3 mm wide with each follicle containing several winged seeds.

Status

The species is listed as

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

in China, but overall when Japanese populations are included ''C. japonicum'' is classified as being lower risk. The Chinese populations were sometimes distinguished in the past as ''Cercidiphyllum japonicum'' var. ''sinense'' Rehder & E.H.Wilson, but this is now generally regarded as not distinct from the species.

Cultivation

Katsura is a popular ornamental tree in Japan as well as elsewhere. In Japan, it is also grown for its timber, which is used for construction and woodworking. Several different

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 are grown, including 'Aureum', 'Heronswood Globe', and 'Ruby'. The following 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 The Award of Garden Merit (AGM) is a long-established annual award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. History The Award of Garden Merit ...

(confirmed 2017): *''C. japonicum'' *''C. japonicum'' ‘Heronswood Globe’ *''C. japonicum'' f. ''pendulum''

Gallery

File:Cercidiphyllum japonicum leaves.jpg, Leaves File:Cercidiphyllum japonicum female flowers.jpg, Female flowers File:Cercidiphyllum japonicum male flowers.jpg, Male flowers File:Cercidiphyllum japonicum immature fruits.jpg, Immature fruit File:Cercidiphyllum japonicum dehisced fruits.jpg, Dehisced fruits File:Cercidiphyllum japonicum ‘Morioka Weeping’.jpg, ''Cercidiphyllum japonicum'' ‘Morioka Weeping’

Arnold Arboretum of Harvard University The Arnold Arboretum of Harvard University is a botanical research institution and free public park, located in the Jamaica Plain and Roslindale neighborhoods of Boston, Massachusetts. Established in 1872, it is the oldest public arboretum in No ...

References

External links

*
''Cercidiphyllum japonicum'' images at the Arnold Arboretum of Harvard University Plant Image Database"Katsura, ''Cercidiphyllum japonicum,'' China 1910."
''Library Featured Images'', Arnold Arboretum of Harvard University website, 14 September 2017. Accessed 1 May 2020. *Friedman, William (Ned)
"Leaves have teeth too."
''Posts from the Collection,'' Arnold Arboretum of Harvard University website, 18 April 2020. Accessed 1 May 2020. *Dosmann, Michael and Andrew Gapinski
"Posts from the Field: Chasing Wilson in Northern Sichuan."
''Arnold Arboretum of Harvard University website'', 16 October 2017. Accessed 1 May 2020. {{Taxonbar, from=Q526549 Saxifragales Trees of Japan Trees of Korea Trees of China Ornamental trees Plants described in 1864