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'Larches' are conifers in the genus ''Larix'', in the family Pinaceae. They are native to much of the cooler temperate northern hemisphere, on lowlands in the far north, and high on mountains further south. Larches are among the dominant plants in the immense boreal forests of Russia and Canada.
They are deciduous trees, growing from 15-50 m tall. The shoots are dimorphic, with growth divided into long shoots typically 10-50 cm long and bearing several buds, and short shoots only 1-2 mm long with only a single bud. The leaves are needle-like, 2-5 cm long, slender (under 1 mm wide). They are borne singly, spirally arranged on the long shoots, and in dense clusters of 20-50 needles on the short shoots. The needles turn yellow and fall in the late autumn, leaving the trees leafless through the winter.
Larch cones are erect, small, 1-9 cm long, green or purple, ripening brown 5-8 months after pollination; in about half the species the bract scales are long and visible, and in the others, short and hidden between the seed scales. Those native to northern regions have small cones (1-3 cm) with short bracts, with more southerly species tending to have longer cones (3-9 cm), often with exserted bracts, with the longest cones and bracts produced by the southernmost species, in the Himalaya.

Contents

Species and classification

Uses

External links and references

Species and classification

There are 10-14 species; those marked '
★ ' in the list below are not accepted as distinct species by all authorities. In the past, the cone bract length was often used to divide the larches into two sections (sect. ''Larix'' with short bracts, and sect. ''Multiserialis'' with long bracts), but genetic evidence (Gernandt & Liston 1999) does not support this division, pointing instead to a genetic divide between Old World and New World species, with the cone and bract size being merely adaptations to climatic conditions. More recent genetic studies have proposed three clades within the genus, roughly corresponding to North American, Eurasian short-bracted, and Eurasian long-bracted (Wei and Wang 2003, 2004), with the notable exception of ''Larix sibirica'', which is a short-bracted species belonging to the long-bracted clade.
;Eurasian short-bracted

★ ''Larix decidua'' (syn. ''L. europaea'') European Larch. Mountains of central Europe.

★ ''Larix gmelinii'' (syn. ''L. dahurica, L. olgensis'') Dahurian Larch. Plains of eastern Siberia.

★ ''Larix kaempferi'' (syn. ''L. leptolepis'') Japanese Larch. Mountains of central Japan.

★ ''Larix principis-rupprechtii'' Prince Rupprecht's Larch
★ . Mountains of northern China (Shanxi, Hebei).
;Eurasian long-bracted

★ ''Larix potaninii'' Chinese Larch. Mountains of southwestern China (Sichuan, northern Yunnan).

★ ''Larix himalaica'' Langtang Larch
★ . Mountains of central Himalaya.

★ ''Larix mastersiana'' Masters' Larch. Mountains of western China.

★ ''Larix speciosa'' Yunnan Larch
★ . Mountains of southwesternmost China (southwest Yunnan), northeast Myanmar.

★ ''Larix griffithii'' (syn. ''L. griffithiana'') Himalayan Larch. Mountains of eastern Himalaya

★ ''Larix sibirica'' Siberian Larch. Plains of western Siberia.
;North American

★ ''Larix laricina'' Tamarack Larch or American Larch. Plains of northern North America.

★ ''Larix lyallii'' Subalpine Larch. Mountains of northwest USA and southwest Canada, at very high altitude.

★ ''Larix occidentalis'' Western Larch. Mountains of northwest USA and southwest Canada, at lower altitudes.
Most if not all of the species can be hybridised in cultivation; the best known hybrid is ''Larix × marschlinsii'' (syn. ''L. × eurolepis'', an illegitimate name), the Dunkeld Larch, which arose more or less simultaneously in Switzerland and Scotland when ''L. decidua'' and ''L. kaempferi'' hybridised when planted together.

Uses

Larch is valued in forestry for its wood, which is tough, waterproof and durable, and top quality knot-free timber is in great demand for building yachts and other small boats. Larch has also been used in herbal medicine; see Bach flower remedies for details.
In central Europe larch is viewed as one of the best wood materials for the building of residences. Planted on borders with birch, both tree species were used in pagan "sagged" cremations. One "sąg" (pron song) of wood was required for a cremation stack. Sąg is used today as a polish forestry unit of approximately 3x1x1m.
In Siberia young larch leaves are harvested in spring, preserved by lactobacillus fermentation, and used for salads during winter.
Larch is used as a food plant by the larvae of a number of Lepidoptera species - see list of Lepidoptera which feed on Larches.
The tree was a running gag in Monty Python sketches. Also Magnets.
Larches are often utilized in bonsai culture, where their knobby bark, small needles, fresh spring foliage and especially autumn colors are appreciated. ''Larix decidua'', ''Larix kaempferi'' and ''Larix laricina'' are the species most commonly trained as bonsai.

External links and references

★ Gymnosperm Database - ''Larix''

★ Internal transcribed spacer region evolution in ''Larix'' and ''Pseudotsgua'' (Pinaceae), D. S. Gernandt & A. Liston, , , American Journal of Botany, 1999

★ Phylogenetic split of ''Larix'': evidence from paternally inherited cpDNA trnT-trnF region, X.-X. Wei & X.-Q. Wang, , , Plant Systematics and Evolution, 2003

★ Recolonization and radiation in ''Larix'' (Pinaceae): evidence from nuclear ribosomal DNA paralogues, X.-X. Wei & X.-Q. Wang, , , Molecular Ecology, 2004