Siberian dwarf pine

A species of the genus Pinus of the family Pinaceae. Introduced into Europe since 1817. Distributed across extensive territories from Anadyr to the Southern Kurils, east to the southern part of Lake Baikal, and west to the lower reaches of the Lena. Grows slowly. Lives up to 250 years.

This is a small prostrate plant with widely spreading branches. The crown depends on the growing location — it can be cup-shaped, prostrate or tree-like. The tree-like form occurs in creeping pines that grow in valleys sheltered from the wind, where they reach 4–5 (7) m in height, with a trunk diameter of 15–18 cm. Most often the cup-shaped crown form is encountered: from a short thick trunk sweep sabre-shaped curved branches. Because of the variety of crown forms, Pinus pumila is classified as a semi-shrub–semi-tree, shrub, or tree-like shrub, and stands of this plant are called creeping krummholz, prostrate forests, or prostrate cedar groves. Root system has a taproot and numerous lateral branches. Later the taproot dies off and lateral roots develop. It can form adventitious roots. Branches pressed to the soil may root.

Shoots and cones are the same as those of Siberian cedar (Pinus sibirica). Young shoots are greenish, covered with coarse, short, gray-brown or reddish hairs, then become gray-brown and smooth. Branches and young shoots emit a strong phytoncidal scent.

Buds are cylindrical, pointed, very resinous, reddish-brown, up to 10 mm long and 4 mm thick. Bud scales are lanceolate, drawn out to a thin point at the tip, and fit tightly together.

Needles thin (0.5–1 mm), medium length (7–10 cm), very dense, narrowly linear, smooth-edged, triangular in cross-section, in bundles of 5, persist on branches for 2–3 years. Needles are slightly twisted, dark green on the outer side and bluish-green on the underside, stomatal lines well expressed.

Flowers in late May – early June. Male catkins are very decorative: up to 15 cm long, intensely green with a red tip. Female cones are ovoid, on a short stalk, violet-purple in color, turning green when ripe.

Mature cones are light-brown or reddish-brown, glossy, 4–5 cm long and 4–4.5 cm wide. They ripen in mid-August in the second year after pollination, fall off without opening, sometimes disintegrate. Seed scales up to 15 mm wide, few, naked, less often slightly pubescent, slightly glossy, the upper edge bent outward, with the apex protruding forward. Seeds are small, 0.9–1.2 cm long and 0.7–1 cm wide, oval, covered with a thin brown woody coat, 15–18 seeds per cone. Mass of 1000 seeds – 98 g. Seed production begins at 20–30 years and continues up to 200 years. Good seed years occur every 2–4 years.

Hardiness zone 1a.

Cultivars: Pinus pumila Glauca, "Draijers Dwarf", "Dwarf Blue", "Globe", "Jeddeloh"

Location: prefers humid air. Does not like dry sandy soils. Grows well on loamy sand and clay loam moist fertile soils. Sensitive to air pollution and dust. Gravel drainage is recommended, with a layer of at least 20 cm.

Planting and pruning: distance between seedlings at least 4–6 m. If the soil is sandy, it is recommended to mix the topsoil with peat and clay in the ratio 2:1:2.

Propagation: propagated by seeds or layering. Seed germination is 80%; stratification is mandatory before sowing. Propagates well in cold regions, but poorly in places where the soil warms up.

Uses: has valuable economic importance. The nuts are eaten fresh, dried and roasted. Wood is used for various handicrafts. Roots and branches are used for extracting resin and turpentine. Turpentine, resin (pitch), young shoots, bark, nut milk, needles, seeds and buds are effectively used in medicine. It is a good reclamation plant — it strongly stabilizes mountain slopes, ravines, river banks, preventing collapses, landslides and mudflows. Also used for protection of plantings along mountain roads. Used for decorating parks, alleys, flowerbeds, in single and group plantings, on rockeries and rock gardens. Tolerates pruning well and can be used as a living hedge. Can be grown in containers.