Scientific name: Larix griffithii J.D. Hooker 1854

Synonyms: Abies griffithiana Lindl. & Gordon, Larix griffithiana (Lindl. & Gordon) Carrière, Larix kongboensis R.R.Mill, Larix sikkimensis Hook. ex Gordon, Pinus griffithiana Voss, Pinus griffithii (Hook.f.) Parl.

Common names: Sikkim larch, Himalayan larch, Binya (Nepalese), Xizang hongshan (Chinese)

Description

Tree to 20(-25) m tall, with trunk to 0.5(-0.8) m in diameter. Bark gray or grayish brown, smooth at first, becoming flaky, and finally breaking up into broad, scaly plates, separated by wide, shallow furrows. Crown conical at first, broadening and becoming egg-shaped with age, rather sparse, with gently rising branches bearing long, hanging twigs. New branchlets quite variable in coloration, from yellowish brown to purplish brown, sometimes waxy, variably hairy, especially in the obvious grooves between the raised leaf bases. Buds small, about 2-3 mm long, reddish brown to purplish brown, smooth or hairy, somewhat resinous. Needles of spur shoots straight or slightly curved, (10-)25-40(-50) on each spur, soft, (1-)2-3.5(-5.5) cm long and (0.6-)1-2 mm wide, bright green, turning bright golden brown in autumn before falling. Midrib prominently raised beneath and slightly so near the base above, with none to two incomplete and inconspicuous lines of stomates on each side above and 3-5 in a narrow white stomatal band on each side beneath. Pollen cones oblong (6-)10-20 mm long, yellowish brown. Seed cones oblong, widest near the middle, (4.5-)5-9(-11) cm long, with 60-100 seed scales, purplish green with bright reddish purple bracts before maturity, ripening dark to light brown with purplish brown bracts, on a short, curved stalk to 5(-7) mm long. Seed scales heart-shaped to elongately heart-shaped with a shallow notch or squared off, curling back a little at maturity, minutely yellowish hairy on the outer face at first. Bracts 15-20 mm long, much longer than the seed scales and curling down conspicuously to cover them, more or less spearhead-shaped, the long bristle tip to 5 mm long and either continuing down with the bract or curled back up. Seed body 4-5 mm long, spotted, the firmly clasping wing another 6-12 mm longer.

In a narrow band through the eastern Himalaya, from central Nepal to the mountains of the borderlands of southwestern China in southeastern Xizang (Tibet) and northwestern Yunnan. Forming pure stands near the alpine tree line or mixed with other conifers and hardwoods through the subalpine cloud forest zone on screes and other rocky soils; (2,400-)3,000-4,000(4,100) m. The climate is moist to wet (summer monsoon), with annual precipitation exceeding 2,000 mm.

Conservation Status

Red List Category & Criteria: Least Concern

Whilst logging of Larix griffithii occurs in some valleys, there are no reports that this has been or is causing a decline in the global population, which is widespread and numerous in large parts of the Himalayas. It is therefore assessed as Least Concern. The typical variety is also Least Concern and not assessed separately. Two varieties are recognized. The typical variety is relatively widespread in the eastern Himalayas while Larix griffithii var. speciosa (W.C.Cheng & Y.W.Law) Farjon is currently only known from NW Yunnan and SE Xizang. The typical variety is not threatened whereas var. speciosa has been separately assessed as Near Threatened. Larix kongboensis R.R.Mill, described from the Yarlung Zangbo river drainage in Xizang, is treated as a synonym of Larix griffithii var. griffithii. It occurs in pure forests up to the tree line, at lower elevations it is often mixed with Abies spectabilis, Abies densa, Pinus wallichiana, Picea spinulosa, Tsuga dumosa and Juniperus sp. Betula utilis and various large species of Rhododendron are the most common broad leaved trees associated with it. Logging would be of potential threat to this species if and where it was unsustainable, i.e. not allowing regeneration to productive age of the same species. Sikkim larch is of minor economic importance as a timber tree due to its occurrence in remote valleys and on high slopes. It was introduced to Britain in the 19th century but was not very successful and remains restricted to a few arboreta and other large gardens with collections of exotic trees, usually in countries or regions with a mild climate and rare occasions of frost. The main problem seems to be early flushing of leaves in regions with erratic warm spells in winter, which then get damaged by 'late' frosts. It would thus be expected to perform better in countries with a more continental, but not extreme winter cold climate. This species is present in some protected areas throughout its range.

References

Farjon, A. (2010). A Handbook of the World's Conifers. Koninklijke Brill, Leiden.
Eckenwalder, J.E. (2009) Conifers of the World: The Complete Reference. Timber Press, Portland.
IUCN Red List of Threatened Species, International Union for Conservation of Nature and Natural Resources. Cambridge, UK /Gland, Switzerland