Cephalotaxus mannii
| Cephalotaxus mannii | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cephalotaxus mannii |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Cephalotaxus mannii | ||||||||||||
| Hook. F. |
Cephalotaxus mannii is a species of plant fromthe head family (Cephalotaxaceae). It is native to southeast Asia.
description
Cephalotaxus mannii grows as an evergreen tree that can reach heights of growth of 20 to 30 meters and chest height diameters of 0.5 to 1.1 meters. There have also been reports of specimens up to 50 meters tall. The light brown to reddish brown trunk bark flakes off. The 8 to 24 centimeters long branches are elliptical to elongated-elliptical in cross-section and about half as wide as they are long.
The relatively thin or leathery, straight or slightly crescent-shaped needles are linear to linear-lanceolate with a length of 1.5 to 4 centimeters and a width of 2.5 to 4 millimeters. They stand on a 0 to 1 millimeter long stem and go from the branches at an angle of 45 to 80 °. The more or less symmetrical base of the needles is blunt to blunt-wedge-shaped, while the point is sharply pointed or briefly spiky. The edges of the needle are slightly bent back. The upper side of the needle is dark green or shiny olive green in color and on the underside of the needle there are 19 to 26 white to bluish white rows of stomas .
The flowering period of Cephalotaxus mannii extends from November to March and the seeds ripen from August to October. The pale yellow, male cones are spherical with a diameter of 4 to 4.5 millimeters and stand on a 1 to 5 millimeter long stem. They are in groups of six to eight and each contain seven to 13 microsporophylls with three to four pollen sacs each . The female cones have a 0.6 to 1 centimeter long stalk and stand together individually or in groups of up to three. They are surrounded by a 2.2 to 3 centimeter long and 1.1 to 1.2 centimeter thick seed coat ( aril ). This is initially green and turns red towards maturity. The obovate to obovate-elliptical seeds are 2.2 to 2.8 centimeters long and have a sharply pointed or spiky tip.
The number of chromosomes is 2n = 24.
Distribution and location
The natural range of Cephalotaxus mannii includes southern and western China, northeast India, Laos , northern Myanmar , northern Thailand and northern Vietnam. In China, the species is found in Xinyi County in southwest Guangdong , Rong County in Guangxi , in Jianfeng Ling , Limu Ling and at Wuzhi Shan in Hainan , in southeastern Xizang and in south and west of Yunnan . The populations in Xizang and Yunnan still need to be examined more closely, it could also be occurrences of Fortune's head yew ( Cephalotaxus fortunei ). In India there are reserves in Arunachal Pradesh , Assam , Manipur , in the in Meghalaya located Khasi Hills , the Jaintia Hills and in the Naga Hills and Nagaland .
Cephalotaxus mannii thrives at altitudes of 500 to 2000 meters. The species grows mainly in mixed forests, subtropical deciduous forests and on wooded slopes. A variety of different soils such as limestone and silicate rock are colonized. It makes silicate soils often mixed stands with Dacrycarpus imbricatus , Nageia wallichiana which Oleanderblättrigen Podocarpus ( Podocarpus neriifolius ) and yew ( Taxus ). On calcareous soils, the species can be found associated with Amentotaxus species, the Fujian cypress ( Fokienia hodginsii ), Nageia fleuryi , Pinus fenzeliana , Podocarpus pilgeri , the Chinese Douglas fir ( Pseudotsuga sinensis ) and the Chinese yew ( Taxus chinensis ).
Cephalotaxus mannii is classified as "Endangered" in the IUCN Red List . The main threat mentioned is the destruction of forests to make them usable for arable farming and the resulting fragmentation of stocks. Furthermore, the targeted felling of large trees for wood production and the removal of the bark for medical use play an important role. The declining total population of the species is difficult to estimate due to the extensive and fragmented distribution area. The population in China is estimated to be less than 15,500 trees, although it is unclear how many of them are fully grown.
use
The wood of the species is used to make high quality furniture, handles for tools and wooden works of art. It has a fine structure, is rather hard, very flexible and easy to work with. It does not split or deform and is considered resistant to insect damage.
Oil can be extracted from the seeds, which is used for painting. The seeds are also used as medicine.
Systematics
It was first described as Cephalotaxus mannii in 1886 by Joseph Dalton Hooker in Icones Plantarum , Volume 16, Page 1523. The occurrences in India are attributed by some authors to the species Cephalotaxus griffithii and the occurrences on the island of Hainan to the species Cephalotaxus hainanensis . These two species hardly differ morphologically from Cephalotaxus mannii .
swell
- Christopher J. Earle: Cephalotaxus mannii. In: The Gymnosperm Database. conifers.org, November 23, 2012, accessed December 19, 2013 .
- Liguo Fu, Nan Li, Thomas S. Elias & Robert R. Mill: Pinaceae . Picea. In: Wu Zhengyi, Peter H. Raven & Hong Deyuan (eds.): Flora of China . Cycadaceae through Fagaceae. Volume 4. Science Press and Missouri Botanical Garden Press, Beijing and St. Louis 1999, ISBN 0-915279-70-3 , Cephalotaxus mannii , pp. 87 ( Cephalotaxus mannii - online - this printed work is online with the same text).
Individual evidence
- ↑ a b c d e Cephalotaxus mannii in the endangered Red List species the IUCN 2013 Posted by: W. Liao & Y. Yang, 2010. Accessed December 21, 2013.
- ↑ a b c d e f g h i Christopher J. Earle: Cephalotaxus mannii. In: The Gymnosperm Database. conifers.org, November 23, 2012, accessed December 19, 2013 .
- ↑ a b c d e f Liguo Fu, Nan Li, Thomas S. Elias & Robert R. Mill: Pinaceae . Picea. In: Wu Zhengyi, Peter H. Raven & Hong Deyuan (eds.): Flora of China . Cycadaceae through Fagaceae. Volume 4. Science Press and Missouri Botanical Garden Press, Beijing and St. Louis 1999, ISBN 0-915279-70-3 , Cephalotaxus mannii , pp. 87 ( Cephalotaxus mannii - online - this printed work is online with the same text).
- ↑ Cephalotaxus mannii at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed December 21, 2013.
- ↑ Cephalotaxus mannii. In: The Plant List. theplantlist.org, accessed December 21, 2013 .
