Ginkgo, maidenhair tree, yin hing 银杏 yin xing [Chinese], イチョウ ichou [Japanese], 은행나무 [Korean]. Variant spellings include ginko and gingo.
This is one of the most relict species on earth, alone in its subclass (Ginkgoidae Engler 1897), order (Gingkgoales Gorozh. 1904), family (Ginkgoaceae Engler 1897), and genus (Ginkgo Linnaeus 1771), and apparently extinct in the wild.
Syn.: Salisburia adiantifolia.
Dioecious deciduous tree, usually with a single straight trunk, up to 30 m tall and 100 cm dbh; crown ovoid to obovoid, tending to be asymmetric, primary branches ascending at ca. 45° from trunk. Bark gray, with short, irregular furrows. Branchlets gray, faintly striate, bearing stubby short shoots at regular intervals, each thick, knoblike or to 3 cm, bearing a cluster of leaves. Buds brown, globose, scales imbricate, margins scarious. Leaves slightly leathery, fan-shaped, with a pattern of radiating veins (not seen in any other tree), usually 2-10 × 2-12 cm, mostly 1.5 times wider than long, light green, stomata on lower side, turning golden and falling each winter. Pollen cones borne on short shoots, catkin-like; bracts absent; pollen spherical. Seeds also on short shoots, maturing in one year, obovoid to ellipsoid, yellow to orange, 2.3-2.7 × 1.9-2.3 cm, mostly 1.1-1.2 times longer than broad, glaucous, rugose, with apical scar, maturing in single season, usually 1 per peduncle, the outer coating softening and giving off a foul odor (which is why female plants are rarely seen). 2n = 24 (Whetstone 1993 and pers. obs.).
Very simply: the leaves do not resemble those of any other tree. See photo at left.
Although Ginkgo biloba is generally agreed to be native to China, it is not clear that the species currently occurs there in the wild. The species is reported to occur naturally in remote mountain valleys in China's Zhejiang province, where as stand has been preserved as the 1018 ha Tian Mu Shan Reserve. This area has supported human activities for approximately 1500 years and it is thus plausible, given the long history of ginkgo as an ornamental species in the area, that its persistence at this site has been facilitated by human actions. Regardless of its origin, the "population is biologically significant by virtue of its long survival in a semi-natural state under conditions of intense interspecific competition. Many of the trees [grow] on disturbance-generated microsites, such as stream banks, steep rocky slopes, and the edges of exposed cliffs. [Many] individuals are multitrunked, consisting of at least two trunks greater than 10 cm in diameter at breast height. Most of these secondary trunks originated from root-like 'basal chichi,' that are produced at the base of trees that have experienced damage from soil erosion or other factors. No Ginkgos less than 5 cm in basal diameter were found in the mature forests of Tian Mu Shan" (Del Tredici et al. 1992).
The great majority of ginkgoes live as ornamentals. In this role the species is nearly cosmopolitan, planted in temperate and subtropical areas around the globe (Whetstone 1993). Hardy to Zone 4 (cold hardiness limit between -34.3°C and -28.9°C) (Bannister and Neuner 2001).
A specimen in Lijiawan, Guizhou, China is 40 m tall with a dbh of 471 cm, and another at Dabao in Gansu is 60 m tall with a 286 cm dbh (Jinxing et al. 1996). One at Yongmun-san temple in South Korea is 36 m tall with a 457 cm dbh (Carder 1995). The largest ginkgo, also the fourth largest tree in Japan is the Kitakanegasawa Ichou, located in Kitakanegasawa aza shiomigata, Fukaura town, Nishitsugaru county, Aomori prefecture. It has a girth of 2,200 cm (Ministry of the Environment 2001). The largest in North America may be a tree planted in 1789 at Pierce Arboretum (now part of Longwood Gardens) in Kennett Square, PA. By 1968 that tree was 105 ft. tall and about 13 ft dbh (Ewan, 1969).
"The unusual shape of the crown, natural resistance to disease, and yellow leaf color in fall make this a favorite street and park tree. Ovulate trees produce an abundance of seeds, which have a particularly obnoxious odor; the planting of ovulate ginkgoes is often discouraged for this reason. Seeds (canned with fleshy outer coat removed) are sold in ethnic markets as "silver almonds" or "white nuts," the gametophyte and embryo being edible. Oils from the outer coat are known to cause dermatitis in some humans" (Whetstone 1993).
An online review of modern and traditional medical uses of the Ginkgo is provided by Foster (1998).
Nearly every arboretum or botanical garden in a temperate or subtropical climate will contain specimens. It is also very commonly planted as a street tree, due to its high tolerance for air pollution. One of the oldest and largest in the West is at the Royal Botanical Gardens, Kew (UK). The supreme specimens, though, are to be found on temple grounds in China, Korea and Japan.
The name ginkgo is derived from the Chinese YIN, silver, and HING, apricot, in reference to appearance of the seed (Whetstone 1993).
Ginkgo is often referred to as a 'living fossil' because nearly identical plants are known from fossils nearly 200 million years old (Whetstone 1993). The fossil record shows that they were formerly a widespread, abundant and diverse group.
Engelbert Kaempfer, during his tenure as a physician with the Dutch East India Company at Deshima from 1690 to 1692, provided the western world with its first description of the ginkgo. By 1730, it was in cultivation in the botanical garden at Utrecht (Folsom 2003). The illustration at left is from the first installment of Siebold and Zuccarini's Flora Japonica, issued in 1835. Philipp Franz von Siebold visited Japan from 1823-1829 as a doctor and scientist in the employ of the Dutch East India Company. During this time he collected thousands of plant and animal specimens, many of new species that were later named for him. Among the conifers, he is commemorated by Tsuga sieboldii.
"Pollination March-April; seeds shed August-November.
"In North America, ginkgo seeds minus the fleshy outer coat have been found beneath various species of trees up to 150 m from the nearest seed-producing ginkgo. The dispersal agents were almost certainly birds, possibly crows. A cache of ginkgo seeds, in association with scats of raccoons [Procyon lotor], was found in a tree crotch about 50 m from the nearest source of the seeds. Apparent animal dispersal of ginkgo requires further study" (Whetstone 1993).
Ginkgo has a vesicular-arbuscular mycorrhiza; one symbiote is Glomus epigaeum (Fontana 1985).
Del Tredici, P., Ling Hsieh and Yang Guang. 1992. The Ginkgos of Tian Mu Shan. Conservation Biology 6(2):202-209.
Engler in Engler et Prantl, Nat. Pflanzenfam. Nachtr. II.-IV: 19. 1897.
Ewan, J. (ed.). 1969. A Short History of Botany in the United States. New York: Hafner Publishing Company, 174pp.
Folsom, J. (ed.). 2003. Plant Trivia TimeLine. PlantEd, Huntington Botanical Gardens, 1151 Oxford Road, San Marino, CA 91108-1299.
Fontana, A. 1985. Vesicular-arbuscular mycorrhizas of Ginkgo biloba L. in natural and controlled conditions. New Phytologist 99(3):441-447.
Foster, Steven. 1998. Ginkgo. Published online at http://www.stevenfoster.com/education/monograph/ginkgo.html, accessed 27-Jan-1999.
Jinxing, L., H. Yushi, and W. Xianpu. 1996. Old Ginkgo trees in China. Pages 32-37 in: International Dendrology Society Yearbook 1995.
Ma Shitu. 1985. The Rare Plants and Flowers of Western Sichuan. 1985. Sichuan People's Press.
Ministry of the Environment. 2001. Big trees survey. http://www.biodic.go.jp/english/kiso/13/13_kyoju_e.html, accessed 2009.11.08.
Whetstone, R. David. 1993. Ginkgo, in the Flora of North America online.
Del Tredici, Peter. 2007. The phenology of sexual reproduction in Ginkgo biloba: ecological and evolutionary implications. Botanical Review 73(4): 267-278.
Del Tredici, Peter. 2000. The evolution, ecology, and cultivation of Ginkgo biloba. Pp. 7-23 in T. van Beek (ed.), Ginkgo biloba. Amsterdam: Harwood Academic Publishers.
Franklin, A.H. 1959. Ginkgo biloba L.: Historical summary and bibliography. Virginia Journal of Science, n. s. 10:131-176.
Hori, T., R.W. Ridge, W. Tulecke, J. Tremouillaux-Guiller, H. Tobe and P. Del Tredici (eds.). 1997. Ginkgo Biloba - A Global Treasure. Tokyo: Springer-Verlag. Contains about 30 articles by various authors on all aspects of Ginkgo and its use.
Jalalpour, J., M. Malkin, P. Poon, L. Rehrmann and J. Yu. 1997. Introduction to the Ginkgoales. Web page hosted by the Museum of Paleontology at the University of California, Berkeley. URL= http://www.ucmp.berkeley.edu/seedplants/ginkgoales/ginkgo.html, accessed 29-Jun-1999.
Page, C.N. 1990. Coniferophytina: Ginkgoaceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. 1+ vol. Berlin etc. Vol. 1, pp. 284-289.
van Beek, Teris A. (ed.). 2000. Ginkgo Biloba. Amsterdam: Harwood Academic Publ. Also contains about 30 articles by various authors on all aspects of Ginkgo and its use.
Photos of the Tianmu Shan ginkgos at http://www.xs4all.nl/~kwanten/tianmu.htm, accessed 2006.11.04.
The ginkgo tree of Otoshi Jinja Shrine (Kyoto Prefecture, Japan). URL=http://www.pref.kyoto.jp/intro/21cent/kankyo/200/jk28e.html, accessed 2000.01.25.
Also, at the same website, The 'Chichi Icho' ginkgo tree of Kokubunji Temple (Kyoto Prefecture, Japan). URL=http://www.pref.kyoto.jp/intro/21cent/kankyo/200/ma3e.html, accessed 2000.01.25
Last Modified 2012-11-28