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 smell it emits during leaf fall.

Description

The tree is deciduous 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
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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 caramel 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). 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 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 cultivars are grown, including 'Aureum', 'Heronswood Globe', and 'Ruby'. The following have gained the Royal Horticultural Society’s 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

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