Sikkim larch

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Sikkim larch
Sikkim larch (Larix griffithii)

Sikkim larch ( Larix griffithii )

Systematics
Class : Coniferopsida
Order : Conifers (Coniferales)
Family : Pine family (Pinaceae)
Subfamily : Laricoideae
Genre : Larches ( Larix )
Type : Sikkim larch
Scientific name
Larix griffithii
Hook f.
illustration

The Sikkim larch ( Larix griffithii Hook. F. , Synonym : Larix griffithiana Carrière ) is a conifer from the larch genus that occurs in the eastern Himalayas and in the adjacent areas. The Sikkim larch is of little economic importance due to its remote distribution area.

description

The Sikkim larch forms 15 to 20 trees with a maximum height of 23 meters with trunks 0.5 to 0.8 meters in diameter at chest height . The trunk is straight or curved and covered with a scaly, gray bark . The crown is broadly conical to pyramidal. The main branches are long and horizontal with ends pointing upwards. The other branches are long, slender, and drooping. The branches are long and slender, with an initially reddish-brown, later gray, yellowish or light brown bark . Young twigs can be hairy or bare, from the third year they are bare. The short shoots have a diameter of 6 to 8 millimeters, are about 3 to 8 millimeters long and have ring-shaped bent up scales.

The leaf buds are 2 millimeters long and 1.5 millimeters wide. They are conical to egg-shaped and resinous, the bud scales are triangular and red-brown. The needles are close together in false whorls of 30 to 50 and more on the short shoots. They are 1.5 to 3.5 centimeters, less often from 1 centimeter and up to 4.5 centimeters long and 1 to 1.8 millimeters wide. They are straight, soft and pliable, green, with an almost flat needle top and a keeled bottom. The needles are shiny and have several interrupted greenish-white stomata on the top and two stomata on the bottom. They turn yellow in autumn.

The yellowish pollen cones stand upright at the ends of short shoots, often numerous on hanging branches. They become 1 to 2 inches long. The seed cones stand upright at the ends of short shoots of hanging branches. Ripe seed cones are 5 to 11 inches long and 2.2 to 3 inches in diameter. They are brown to light brown, cylindrical to cylindrical-ellipsoidal. The seed scales are obovate, more or less flat and in the center of the cone 1.1 to 1.4 centimeters long and just as wide. The base is hairy on the outside, the scalloped edge is serrated towards the tip. The tip is trimmed or slightly edged. The cover scales are ovate to obovate-lanceolate. They are longer than the seed scales, 5 to 7 millimeters wide and curved back. The seeds are whitish gray with irregular red spots, obliquely obovate and with wings about 10 millimeters long. Pollination takes place from April to May, the seeds ripen in October.

The number of chromosomes is 2n = 24.

Distribution and ecology

The distribution area of ​​the Sikkim larch is in the eastern Himalayas, in Bhutan , Nepal , in the Indian state of Sikkim and in southern and eastern Tibet . It grows in the foggy zone of the mountains at altitudes of 2400 to 4100 meters, more rarely at altitudes above 1800 meters. They are found on moraines and other gravelly soils. The climate is influenced by the summer monsoon with annual rainfall of over 2000 millimeters. In higher altitudes up to the tree line it grows in pure stands, in lower altitudes together with the Himalayan fir ( Abies spectabilis ), Abies densa , the teardrop pine ( Pinus wallichiana ), the Sikkim spruce ( Picea spinulosa ), the Himalayan hemlock ( Tsuga dumosa ), various species of juniper ( Juniperus ), the Himalayan birch ( Betula utilis ) and various species of the genus Rhododendron .

In the Red List of the IUCN , the Sikkim larch will be deemed not at risk ( "Lower Risk / least concern"). It is pointed out, however, that a new check of the risk is necessary.

Systematics and research history

The Sikkim larch ( Larix griffithii Hook.f. ) is a species of the larch genus . Two varieties are recognized:

  • The variety Larix griffithii var. Griffithii has yellowish or light brown, hairy shoots and 1.5 to 3.5 centimeters long and 1 to 1.2 millimeters wide needles. Needles from 1 centimeter or up to 3.8 centimeters in length are less common. The cover scales of the seed cones are strongly bent back. Its distribution area is in the eastern Himalayas, from eastern Nepal via Sikkim and Bhutan to the Indian state of Arunachal Pradesh and in Tibet.
  • The variety Larix griffithii var. Speciosa (WCCheng & YWLaw) Farjon (Syn .: Larix speciosa W.C.Cheng & YWLaw ) has darker-colored and bald long shoots and thicker short shoots. The needles are 2.5 to 4.5 inches long and 1 to 1.5 millimeters wide. The cover scales of the seed cones are narrower and less strongly bent back. The variety is described as Larix speciosa as a separate species. However, the continuous transition between the two varieties speaks against the species status; for two separate species the transition should be less continuous.

The species was first described in 1854 by the English botanist Joseph Dalton Hooker as Larix griffithii in the Himalayan Journal . A year later, the French botanist Élie-Abel Carrière published the species under the synonym Larix griffithiana in the French Traité Général des Conifères . The synonym is used with about the same frequency as the actual species name; However, the older name is valid. The specific epithets griffithii and griffithiana are reminiscent of William Griffith , who discovered the species in Bhutan. With his other finds, as director of the Botanical Gardens of Calcutta, he created an extensive herbarium which is now kept in the Royal Botanic Gardens in Kew (London) .

use

The Sikkim larch is of little economic importance as it is only found in remote valleys and in the mountains. The wood is used as construction timber, for pits and railroad tracks, and for making furniture. The rind contains tannins . The tree is used for afforestation. It was introduced in Great Britain in the 19th century but did not become widespread and was confined to a few gardens. There it is attacked by short-term warm phases in winter because it drives needles that are damaged by later frost.

proof

literature

  • Aljos Farjon: A Handbook of the World's Conifers . tape 1 . Brill, Leiden-Boston 2010, ISBN 90-04-17718-3 , pp. 486-488 .
  • Steve Cafferty: Cosmos Atlas Trees of the World . Franckh-Kosmos, Stuttgart 2008, ISBN 978-3-440-10983-0 , p. 66 .

Individual evidence

  1. Illustration from Joseph Dalton Hooker, John Fergusson Cathcart, Walter Hood Fitch: Illustrations of Himalayan Plants , p. 101. online
  2. ^ German name after Steve Cafferty: Kosmos-Atlas Trees of the World , p. 66
  3. a b c d e f g h i j Farjon: A Handbook of the World's Conifers , pp. 486-488
  4. a b c d e Larix griffithii. In: Flora of China Vol. 4. www.eFloras.org, p. 33 , accessed on July 31, 2011 (English).
  5. ^ Tropicos. [1]
  6. Larix griffithii in the endangered Red List species the IUCN 2011. Posted by: Conifer Specialist Group, 1998. Accessed July 31, 2011th
  7. a b Larix griffithii. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed August 12, 2011 .
  8. Larix speciosa. In: Flora of China Vol. 4. www.eFloras.org, p. 34 , accessed on August 12, 2011 (English).
  9. Larix griffithiana. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed August 12, 2011 .
  10. Christopher J. Earle: Larix griffithii. In: The Gymnosperm Database. Retrieved August 13, 2011 .

Web links

Commons : Sikkim larch  - collection of images, videos and audio files