Chinese Douglas fir

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Chinese Douglas fir
Branch of Pseudotsuga sinensis var. Sinensis with needles and seed cones

Branch of Pseudotsuga sinensis var. Sinensis with needles and seed cones

Systematics
Class : Coniferopsida
Order : Conifers (Coniferales)
Family : Pine family (Pinaceae)
Subfamily : Laricoideae
Genre : Douglas firs ( Pseudotsuga )
Type : Chinese Douglas fir
Scientific name
Pseudotsuga sinensis
Dode

The Chinese Douglas fir ( Pseudotsuga sinensis ) is a conifer of the genus Douglas fir in the pine family (Pinaceae). The species is assigned to three varieties, which have their main distribution area in China.

description

The Chinese Douglas fir is a tree up to 50 meters high with a chest height diameter of up to 2 meters. The trunk is more or less straight and columnar or forked. The gray trunk bark is rough and very scaly. The branches are spreading and are almost vertical near the tip. They form a rounded or broadly spreading crown. The twigs are thin, reddish brown in the first year and turn gray later. They are mostly short haired in different furrows, later become bald and have small, slightly raised, round or angular leaf scars. The non-resinous or only slightly resinous leaf buds are ovate or conical, 4 to 8 millimeters long and 3 to 4.5 millimeters in diameter. The bud scales are triangular, pointed, shiny red-brown and are shed in the second year.

Needles

The needles are comb-shaped, are 2.5 to 4, rarely from 0.7 to 5 centimeters long and 1.5 to 2.1, rarely from 1 to 3 millimeters wide. They are slightly twisted or curved at the base and are otherwise straight, linear, flattened, with an edged or blunt tip and a furrowed top along the side. The stomata are arranged in two greenish-white bands on the underside of the needle, the top is dark green.

Cones and seeds

The pollen cones are yellowish, 1 to 1.5 centimeters long and hang fully grown from the branches. The seed cones stand on stems 1 to 2.5 centimeters long, they are ovate or oblong, 4 to 6.5 centimeters long (rarely from 2 to 5.5 centimeters) and have a diameter of 3.5 to 5 centimeters with the scales open (rarely from 2 and up to 5.5 centimeters). They are reddish when young and later turn reddish brown or brown. They stay on the tree for several years until they fall off. The seed scales are rhombic-rounded, rounded to kidney-shaped, convex, slightly thicker and lignified at the end, initially slightly hairy, later bald, in the center of the cone 2.5 to 3 centimeters long and 3 to 3.5 centimeters wide. The base is short stalked, the outer areas are entire. The cover scales are tongue-shaped, linear with a three-lobed tip, the middle one being somewhat larger. They are 3.5 to 4 inches long, protruding and curved back. The seeds are wedge-shaped-ovate 8 to 12 millimeters long and 5 to 8 millimeters wide, light brown with dark spots. The seed wing is ovate 8 to 15 millimeters long, brown with dark spots. Pollination takes place in April, the cones ripen from October to November.

Chromosome number

The number of chromosomes is 2n = 24.

Distribution and ecology

The distribution area of ​​the Chinese Douglas fir extends in China over south Anhui , Fujian , southwest Guangxi , Guizhou , west Hubei , north Hunan , north and south Jiangxi , Sichuan , the northeast of Tibet , Yunnan and Zhejiang . They can also be found in Taiwan and in northern Vietnam. There it grows at various altitudes of lower to medium-high mountains, in the southeast of China from 600 to 1200 meters and on Taiwan from 1000 to 2700 meters. In Sichuan and Yunnan they can also be found at over 3000 meters, the highest tree was found at 3300 meters. In southeast China it grows on red and yellow soil . It needs a warm to moderate, humid climate with annual rainfall of 1000 to 2000 millimeters.

In the Red List of the IUCN , the Chinese Douglas as endangered ( "Vulnerable") is performed. However, please note that a new classification is pending. The cause of the endangerment is the heavy use and the destruction of the habitat.

Systematics and research history

The Chinese Douglas Fir ( Pseudotsuga sinensis ) is a kind from the kind of Douglas fir ( Pseudotsuga ) in the family of Pinaceae (Pinaceae). It was in 1912 by the French botanist Louis-Albert Dode (1875-1943) in the Bulletin da la Société Dendrologique de France and in the communications of the German Dendrological Society , Berlin firstdescribed . The specific epithet sinensis chosen by him refers to the distribution area in China.

There are three varieties :

  • Pseudotsuga sinensis var. Sinensis
  • Pseudotsuga sinensis var. Brevifolia (WC Cheng & LK Fu) Farjon & Silba
  • Pseudotsuga sinensis var. Gaussenii (flous) Silba

Variety Pseudotsuga sinensis var. Sinensis

The needles are 1.3 to 4 inches long and 1.5 to 3 millimeters wide, the buds are ovate-conical, more or less pointed and 4 to 7 millimeters long with a diameter of 3 to 4 millimeters. The seed cones are 4.5 to 8 centimeters long and have a diameter of 3 to 5 centimeters when the scales are open. The seed scales are rhombic round to almost round. The distribution area of ​​the variety is in southern Anhui, in Chongquing , Fujian, Guizhou, in western Hubei , in northern Hunan , in northern and southern Jiangxi, in Sichuan, Yunnan, Zhejiang and on Taiwan. Due to the intensive use, particularly large, fully grown trees are rare and can only be found in areas that are difficult to access. Although the species can be found in a very large area, it is rare and only a small part of the range is protected. The IUCN classifies this variety as “Vulnerable”, although a reassessment is pending. It should be noted that the range is divided into many small isolated areas. The situation in Taiwan is particularly discussed. The habitat there has been greatly reduced by apple and peach plantations, and the Chinese Douglas fir, as in the People's Republic of China, is heavily used.

The taxa Pseudotsuga forrestii (also viewed as a variety Pseudotsuga sinensis var. Forrestii (Craib) Silba ) and Pseudotsuga wilsoniana (also viewed as a variety Pseudotsuga sinensis var. Wilsoniana (Hayata) LK Fu & Nan Li ), previously classified as separate species , are only valid as synonyms for Pseudotsuga sinensis var. sinensis .

Variety Pseudotsuga sinensis var. Brevifolia

The needles are 0.7 to 1.5, rarely up to 2 centimeters long and 2 to 3, rarely up to 3.2 millimeters wide. They are thus significantly shorter but somewhat wider than in the sinensis variety . The buds are ovate, blunt, 4 to 5 millimeters long and 3 millimeters in diameter. The seed cones are slightly smaller, 3.7 to 6.5 inches long and when opened, 3 to 4 inches wide. The seed scales are rhombic round to almost round. The range of the variety is in the southwest of Guangxi , in Guizhou and possibly in the north of Vietnam. In the case of the occurrences in Vietnam, it is unclear whether they should not be included in the sinensis variety . Brevifolia can be found scattered on southern slopes and on mountain peaks on calcareous, rocky subsoil at altitudes between 1000 and 1300 meters. The variety only grows in a limited area in the limestone mountains of southwest China, with very little data available on the exact range and frequency of the variety. Trees can usually only be found in very inaccessible areas, all other stands have been cut down. It is therefore also classified by the IUCN as endangered ("Vulnerable"), although a reassessment is still pending.

The variety was described in 1975 by Wan Chun Cheng and Li Kuo Fu in the Acta Phytotaxonomica Sinica as a separate species Pseudotsuga brevifolia . The taxon is also found under this name in the Flora of China , but it was assigned in 1990 by Aljos K. Farjon and John Silba in the journal Phytologia as a variety of the species Pseudotsuga sinensis .

Variety Pseudotsuga sinensis var. Gaussenii

The needles are 1.6 to 3 inches long and 1.7 to 2 millimeters wide. The buds are ovate-conical and more or less pointed, 4 to 5 millimeters long and 3 millimeters in diameter. The seed cones are the smallest of the three varieties and are 3.5 to 5.5 inches long and have a diameter of 2 to 3.5 inches. The seed scales are broadly fan-shaped to kidney-shaped. Natural occurrences are in southeastern Anhui , possibly in Fujian , in Jiangxi , Sichuan and in the north and northwest of Zhejiang . Due to heavy use, large trees are rare and the variety is rarely found overall. Stocks only exist in inaccessible mountain areas. The IUCN also lists the variety as endangered ("Vulnerable"), but a larger population in Zhejiang Province has been placed under protection.

The variety was described by Fernande Flous (* 1908) in 1936 in the Bulletin de la Société d'Histoire Naturelle de Toulouse as a separate species Pseudotsuga gaussenii and classified as a variety of Pseudotsuga sinensis by John Silba in the journal Phytologia in 1990 .

use

The wood of the Chinese Douglas fir is used as lumber for building bridges, for the manufacture of furniture and wood fiber . The trees were used intensively, so that large specimens are rare. Also, since it is difficult to cultivate on a large scale, its economic importance decreases. It was introduced in Europe by Ernest H. Wilson , George Forrest and Camillo Schneider at the beginning of the 20th century, but it is rarely cultivated and is mostly confined to arboretums and botanical gardens .

proof

literature

Individual evidence

  1. ^ German name after Cafferty: Kosmos-Atlas Trees of the World , p. 64
  2. ↑ a b c d Farjon: A Handbook of the World's Conifers , Volume 2, p. 934
  3. ^ Liguo Fu, Nan Li, Thomas S. Elias, Robert R. Mill: Pseudotsuga sinensis . In: Wu Zheng-yi, Peter H. Raven (Ed.): Flora of China . Volume 4: Cycadaceae through Fagaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 1999, ISBN 0-915279-70-3 , pp. 38 (English).
  4. ^ Tropicos. [1]
  5. ↑ Pseudotsuga sinensis in the endangered Red List species the IUCN 2011. Posted by: Conifer Specialist Group, 1998. Accessed November 26, 2011th
  6. ↑ Pseudotsuga sinensis. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed November 26, 2011 .
  7. ^ Farjon: A Handbook of the World's Conifers , Volume 2, p. 933
  8. ↑ a b c Farjon: A Handbook of the World's Conifers , Volume 2, p. 935
  9. ↑ Pseudotsuga sinensis var. Sinensis in the endangered Red List species the IUCN 2011. Posted by: Conifer Specialist Group, 1998. Accessed November 26, 2011.
  10. ^ Liguo Fu, Nan Li, Thomas S. Elias, Robert R. Mill: Pseudotsuga forrestii . In: Wu Zheng-yi, Peter H. Raven (Ed.): Flora of China . Volume 4: Cycadaceae through Fagaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 1999, ISBN 0-915279-70-3 , pp. 38 (English).
  11. ↑ Liguo Fu, Nan Li, Thomas S. Elias, Robert R. Mill: Pseudotsuga sinensis var. Wilsonia . In: Wu Zheng-yi, Peter H. Raven (Ed.): Flora of China . Volume 4: Cycadaceae through Fagaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 1999, ISBN 0-915279-70-3 , pp. 38 (English).
  12. ↑ Pseudotsuga sinensis var. Brevifolia in the Red List of Threatened Species of the IUCN 2011. Posted by: Conifer Specialist Group, 1998. Accessed November 26, 2011.
  13. ↑ Pseudotsuga brevifolia. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed November 27, 2011 .
  14. ^ Liguo Fu, Nan Li, Thomas S. Elias, Robert R. Mill: Pseudotsuga brevifolia . In: Wu Zheng-yi, Peter H. Raven (Ed.): Flora of China . Volume 4: Cycadaceae through Fagaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 1999, ISBN 0-915279-70-3 , pp. 38 (English).
  15. ↑ Pseudotsuga sinensis var. Brevifolia. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed November 27, 2011 .
  16. ^ Farjon: A Handbook of the World's Conifers , Volume 2, pp. 935-936
  17. ↑ Pseudotsuga sinensis var. Gaussenii in the endangered Red List species the IUCN 2011. Posted by: Conifer Specialist Group, 2000. Accessed November 26, 2011.
  18. ^ Pseudotsuga gaussenii. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed November 27, 2011 .
  19. ↑ Pseudotsuga sinensis var. Gaussenii. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed November 27, 2011 .

Web links

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