Larches are deciduous in the genus Larix, of the family Pinaceae. Growing to as much as tall, they are native to the cooler regions of the Northern Hemisphere. They grow in lowland forests in the far north, and high in mountains further south. Larches are among the dominant plants in the Taiga of Siberia and Canada, making them the most abundant genus of trees on earth. Larch wood is tough and relatively durable. The wood is used in Boat building, cladding, decking, garden furniture, fence, and construction. Products extracted from larch include arabinogalactan, rosin, turpentine, and an essential oil.
Etymology
The English name
larch was recorded in 1548 by the botanist William Turner. It derives from the German Lärche, in turn from the Middle High German larche, which is conjectured to derive from an unrecorded Old High German name for the tree,
*larihha. That derives from the
Latin name of the tree,
Larix.
The Latin name probably was loaned from a
Gaulish language spoken in the
Alps.
Description
File:Larch botanical illustration labelled.svg|Larch botanical illustration labelled
Habit and foliage
The tallest species,
Larix occidentalis, can reach . Larch tree crowns are sparse, with the major branches horizontal and in whorls; the second and third order branchlets are roughly horizontal in some species,
pendulous in others. Larch shoots are dimorphic, with needle-like leaves borne singly on long shoots with several
, and in dense clusters of 20–50 needles on short shoots with only a single bud.
Larch wood is resinous. The bark of young trees is smooth; that of older trees is thick and scaly. Larches are among the few
deciduous conifers, which are usually evergreen.
File:Larix occidentalis Abies lasiocarpa.jpg| Larix occidentalis can reach in height. Oregon
File:Larix decidua leaf dimorphism singly or in dense clusters on same tree.jpg|Larch shoots (here Larix decidua) are dimorphic, with long shoots with widely spaced needles, and short shoots with dense clusters of leaves.
File:10 31 2008 Stand of Tamarack.jpg|Larches, like this
Larix laricina in Vermont, are deciduous, dropping their leaves in autumn.
Cones
The male (
pollen) cones are small, on the ends of shoots that die after pollination.
The female (seed)
conifer cone are small, typically erect, and take 4–7 months to reach maturity after pollination.
The seed scales spread apart when mature, allowing the winged seeds, two per scale, to fall out.
The leaflike
bract scales can be either long and visible (exserted) or short and hidden between the seed scales.
File:Flowers of Japanese larch emerging.jpg|Male (above) and female (below right) cones of Larix kaempferi emerging in spring, Japan
File:Larix decidua needles and male cones.JPG| Larix decidua male cones, Scotland
File:Larix decidua female cones.jpg| Larix decidua female cones
File:SubalpineLarch 7769.jpg| Larix lyallii autumn foliage and cone, Washington state
File:Larix griffithii, Yathang, Sikkim, India 1.jpg| Larix griffithii foliage and cone, Sikkim
The Chromosome is 2n = 24, similar to that of most of the other species of the family Pinaceae.
Distribution
The genus
Larix is present in all the temperate-cold zones of the Northern Hemisphere, from North America to northern
Siberia passing through Europe, mountainous China and Japan. The larches are important forest trees of Russia,
Central Europe, the United States and Canada. They require a cool and fairly humid climate, and for this reason, they are found in the mountains of the temperate zones, while in the northernmost boreal zones, they are also found in the plains. Larch trees go further north than all, reaching in North America and Siberia the
tundra and polar ice.
The larch species
Larix gmelinii is the world's most northerly-growing tree, at 75° north in the
Taymyr Peninsula.
File:Larch distribution.svg|Worldwide distribution of genus Larix.
Positions are diagrammatic.
The larches are pioneer species not very demanding of the soil and they are very long-lived trees. They live in pure or mixed forests together with other conifers or more rarely with broad-leaved trees. In 1965, larch constituted 40.2% of the forests of the Soviet Union and had a cumulative volume of 28,450 million m³, (28.45 cubic kilometres, or 6.8 cubic miles) of solid wood; by a wide margin, the most abundant genus of trees on earth.
File:Nature in Khanty-Mansiya.jpg| Larix sibirica in Khanty-Mansiya, Russia
File:Raven Ridge - Flickr - brewbooks (2).jpg| Larix lyallii forest in Washington state
Evolution
External phylogeny
The genus
Larix belongs to the subfamily
Laricoideae, which includes the Douglas firs, genus
Pseudotsuga. The genus
Cathaya was included in some older studies,
but based on
transcriptome analysis, is now considered closer to
Pinus and
Picea.
The split of
Larix from
Pseudotsuga occurred about 45 million years ago.
Taxonomy and internal phylogeny
The genus
Larix was described by the English botanist
Philip Miller in 1754.
In the 20th century, cone bract length was used to divide the larches into two sections (sect.
Larix with short bracts, and sect.
Multiserialis with long bracts), but genetic evidence does not support this division, indicating instead that the cone and bract size are merely adaptations to climatic conditions.
Late 20th century and early 21st century genetic studies proposed three groups within the genus, with a primary division into North American and Eurasian species, and a secondary division of the Eurasian into northern short-bracted species and southern long-bracted species; there was dispute over the position of Larix sibirica, a short-bracted species which is placed in the short-bracted group by some of the studies and the long-bracted group by others. Ten species and one natural hybrid of larch are accepted by Plants of the World Online (POWO), following the conservative treatment in Farjon (2010); several others are accepted by the Flora of China.
However, a 2025 study by Qiu and colleagues cast doubt on the species circumscriptions accepted by Farjon and the POWO; it showed that Larix himalaica is close to L. griffithii as geographic parsimony would predict (and not to L. potaninii as Farjon believed), and that L. speciosa is distinct and should be treated as a separate species. Conversely, they found that L. mastersiana was embedded within L. potaninii and may be best synonymised with it. Their results showed that the division between Old World and New World species as suggested by earlier studies is not correct, but rather, the primary divide is between the high-latitude circumboreal species, and the low latitude Sino-Himalayan species group, as shown in the cladogram.
Hybrids
Most larches can be hybridised in cultivation;
these hybrids are not discussed by POWO as they are not of natural occurrence.
Larix × marschlinsii (syn.
L. ×
eurolepis), the
Dunkeld larch, a hybrid of
L. decidua ×
L. kaempferi, is by far the best known: it is of major importance in
forestry in northern Europe. It arose more or less simultaneously in Switzerland and Scotland in 1901–1904.
Other named hybrids include
Larix ×
pendula (
L. decidua ×
L. laricina),
and
Larix ×
eurokurilensis (
L. decidua ×
L. gmelinii).
[
]
Ecology
Species interactions
Larches are associated with some fungal species, including species which primarily or only associate with larch. One of the most prominent of these is the larch bolete Suillus grevillei. Larch is used as a food plant by the of moths such as the larch pug, Eupithecia lariciata.
The large larch bark beetle, Ips cembrae, can be harmful to already-weakened larch trees, but is in general a less serious threat than a related species, the spruce bark beetle Ips typographus, is to .
File:Suill.grev.jpg|The larch bolete Suillus grevillei, a mushroom, always grows under larches.
File:Lärchenborkenkäfer Draufsicht.png|Adult large larch bark beetle, Ips cembrae
File:Lärchenborkenkäfer Brutbild.JPG|Galleries of Ips cembrae under the bark
Diseases
Larches are prone to the fungus canker disease Lachnellula spp. (larch canker); this is a problem when late spring frosts cause minor injuries to the tree, allowing entry to the fungal spores. In Canada, this disease was first detected in 1980; it kills Larix laricina of any age.[ European larch canker Natural Resources Canada, accessed 23 April 2021]
Larches are vulnerable to Phytophthora ramorum. In 2013 the disease appeared in the Afan Forest Park in south Wales.
Laricifomes officinalis is another mushroom found in Europe, North America and northern Asia that causes internal wood rot. It is almost exclusive to the genus Larix. Other diseases are caused by mushrooms, fungal rusts, and bacteria.
Uses
Larch timber has many uses, including Boat building, exterior cladding, and interior panelling. Outdoor uses include fence, gates, decking, garden furniture, and playground equipment. Since the heartwood is strong, durable, and available in large sizes, it is used for structures such as agricultural buildings. The Savill Building in Windsor Great Park has a timber roof shell made of many relatively thin laths, interlocking to provide strength. The wood is used, too, as fuel in industrial biomass energy plants. The bark used as a mulch in horticulture. Arabinogalactan, used in animal feed, cosmetics, and medicines, is extracted from heartwood. Larch trees can be tapped for liquid to be distilled into Venice turpentine. The tree yields rosin for violin bows and an essential oil used in aromatherapy. European Standard EN 350-2 lists larch as slightly to moderately durable.[European Standard EN 350-2 (1994); Durability of Wood and Wood-based Products – Natural Durability of Solid Wood: Guide to natural durability and treatability of selected wood species of importance in Europe]
Dunkeld larch is widely grown as its timber is durable and strong, and the tree tolerates poor weather better than non-hybrid larches.
File:Concordia molen Ede stijl korbeel.jpg|Larch wood in use to restore the Concordia mill, Netherlands
File:Saville Building roof interior long.jpg|The roof shell of the Savill Building is made of interlocking larch laths.
In culture
The Roman architect Vitruvius conjectured in his De architectura that the Latin name for timber from the tree, larigna, came from the town of Larignum, where Julius Caesar, besieging the town, supposedly discovered the larch.
More recently, the Monty Python comedy troupe filmed a sketch with three schoolboys shown slides of the larch and asked which trees they were able to identify.
File:Larch, from The Park and the Forest James Duffield Harding 1841.jpg| Larch, from The Park and the Forest, James Duffield Harding, 1841
File:James Ward - Larch Tree - Google Art Project.jpg| Larch tree pencil drawing,
James Ward, before 1859
File:Franz Marc, Lärchenbäumchen.jpg| Larch sapling,
Franz Marc, 1908
File:Berry Lärchen im Schnee.jpeg| Larch in first snow,
Peter Robert Berry, 1914
File:Lovis Corinth Lärche am Waldsee 1923.jpg| Larch by forest lake,
Lovis Corinth, 1923
File:Lovis Corinth Walchensee mit Lärche 1923.jpg| Walchensee with fountain,
Lovis Corinth, 1923
File:Stamp of Russia 2013 No 1684 Larix cajanderi.jpg|Russian 15 rouble stamp, 2013,
Larix cajanderi
Further reading
-
Quote from p. 729.
-
Phillips, D. H., & Burdekin, D. A. (1992). Diseases of Forest and Ornamental Trees. Macmillan .
External links