Cookies on Plantwise Knowledge Bank

Like most websites we use cookies. This is to ensure that we give you the best experience possible.

Continuing to use www.plantwise.org/KnowledgeBank means you agree to our use of cookies. If you would like to, you can learn more about the cookies we use.

Plantwise Knowledge Bank
  • Knowledge Bank home
  • Change location
Plantwise Technical Factsheet

common larch (Larix decidua)

Description

Larches are deciduous conifers, shedding their needles in winter. Their soft, fine needles, grouped in fascicles on short shoots, distinguish them from other boreal conifers. All larch species have similar morphological features, especially for their vegetative traits. The surest way to recognise the different larches is by comparing the morphological features of the female cones and to some extent, by examining the bark colour of young branchlets (Ostenfeld and Larsen, 1930; Lepage and Basinger, 1991; Vidakovic, 1991).

General habit and size

European larch is an elegant tree with a broad pyramidal crown, becoming wider and irregular as it gets older. Its straight stem sometimes shows some tendency toward basal sweep. Branchlets are somewhat drooping. The bark of young European larch seedlings is whitish grey or yellowish-grey, allowing to distinguish it in the nursery from Japanese larch, which has a reddish brown bark (Boudier, 1981). A mature tree can reach a height of over 20 m, with a diameter at breast height of 60 cm or more. The crown can reach a width of 15 m. The tree has a life span of up to 2 centuries, although it can be harvested for timber at around 40 years old.

Foliage

The needles of European larch, grouped in fascicles of 30 to 40, measure 10 to 38 mm long and 0.5 mm wide, are keeled, and have several rows of stomata (Lepage and Basinger, 1991). As they unfold, the young leaves have a delicate, mossy fragrance (Plants, 1997). Dried leaves of European larch, however, lack the distinctive, sweet fragrance of Siberian larch (Ostenfeld and Larsen, 1930). Before being shed from the tree in the autumn, the needles take on a spectacular golden yellow colour.

Inflorescences, flowers and fruits

The mature female cones of European larch are ovoid, 15 to 60 mm long and 15 - 24 mm wide, with 40 to 50 scales (Lepage and Basinger, 1991). During the flowering season, the cone bracts are crimson red (rarely green), and much longer than the cone scales (Ostenfeld and Larsen, 1930). On mature cones, however, the bracts are hidden by the cone scales. The seeds measure 1 to 4 mm long by 2.5 to 3 mm wide, with a wing 8 mm long by 4 mm wide (Lepage and Basinger, 1991).

The slight variations in cone morphology throughout the distribution range of European larch have led certain authors to separate the species into several geographical races or varieties (Ostenfeld and Larsen, 1930; Vidakovic, 1991).

Phenology

Depending on local climatic conditions, flowering of European larch begins between late March and early May, before the opening of the leaf buds (Chalupa, 1991; Stipanicic and Mercier, 1993). Within a given tree, pollen is usually shed from the male cones one or two days before the female flowers become receptive. Leaves appear during or just after flowering, and usually fall around October. Seeds are mature in September or October (Vidakovic, 1991). Cones open in the autumn and seeds are dispersed throughout the winter and following spring. The empty cones usually persist on the tree for 2 to 3 years.

Zoomed image