Larch

Larch

About 10–14; see text

Larches are conifers in the genus Larix, in the family Pinaceae. Growing from 20 to 45 m tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains further south. Larch are among the dominant plants in the immense boreal forests of Russia and Canada.

Although a conifer, the larch is a deciduous tree and loses its leaves in the autumn. The shoots are dimorphic, with growth divided into long shoots typically 10–50 centimetres 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 centimetres long, slender (under 1 cm 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 Himalayas.