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| Larch | ||||||||||||
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Siberian Larch, Larix sibirica | ||||||||||||
| Scientific classification | ||||||||||||
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| Species | ||||||||||||
| About 12; see text |
Larches are conifers in the genus Larix, in the family Pinaceae. They are deciduous trees, growing from 15-50 m tall, and 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.
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 conesA cone (in formal botanical usage: strobilus plural strobili) is an organ on plants in the division Pinophyta ( conifers) that contains the reproductive structures. The familiar woody cone is the seed-producing female cone. The male cones, which produces 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) with exserted bracts, with the longest cones and bracts produced by the southernmost species, in the HimalayaTibetan plateau and the Taklamakan plain to the north. The Himalaya (the Himalayan Range is a mountain range in Asia, separating India and the Northern Areas of Pakistan on the south and southwest from the vast Tibetan plateau (now part of China) on the n. In the past, the 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 does not support this division, pointing instead to a genetic divide between Old WorldThe Old World consists of those parts of Earth known to Europeans before the voyages of Christopher Columbus: Europe, Asia, and Africa. The term is in distinction for the New World, meaning the Americas. Although the interiors of Asia and Africa were not and New WorldThe New World is one of the names used for the continents of North and South America and adjacent islands collectively, in use since the 16th century. The continents were new to the Europeans, who knew the world consisting only of Europe, Asia, and Africa species, with the cone and bract size being merely adaptations to climatic conditions.