Siberian spruce

Synonyms: ель печорская, Abies excelsa ssp. alpestris Brugger, Picea abies ssp. alpestris (Brugger) Domin, Picea abies ssp. obovata (Ledeb.) Domin, Picea abies var. alpestris (Brugger) P.A. Schmidt, Picea alpestris (Brugger) Stein, Picea obovata ssp. petchorica Govor., Picea petchorica Govor.

Siberian spruce – a species of evergreen trees of the genus Spruce in the family Pinaceae. In the wild it grows in regions from northern Europe to Magadan Oblast (Russia). It is one of the main forest-forming species in Siberia. It also occurs on the Scandinavian Peninsula, in northern Mongolia, on the Scandinavian Peninsula, and in northern Manchuria (China). It grows mainly in mixed forests, less often as a forest-forming species.

It is a large tree up to 30 m in height, with a trunk diameter 70 cm (1 m). Tree height and growth rate depend on light exposure. Crown narrow-pyramidal or pyramidal; in free-standing specimens the crown begins at the base.

Shoots are reddish-brown, yellow-gray, more rarely almost white, often pubescent with sparse short reddish hairs. Branches and shoots are grooved, with numerous stubs of leaf scars that sit on long leaf cushions, acute above and elongated downward. Buds ovoid or oval, non-resinous, reddish-brown; bud scales appressed, the lower ones with an awl-shaped tip. Bark dark gray, almost black, fissured.

Needles short, 10-15 (20) mm long and up to 1 mm wide, quadrangular, pointed, sharp, glaucous-green, denser and shorter than in Norway spruce. Stomatal bands weakly expressed, 2-3 on each side, giving the needles a bluish tint. Needles are attached to special outgrowths of the bark, so-called leaf cushions, which are well visible after their fall. Retained on the tree for 6-7 years.

Begins to flower at about 8 years old. Flowering period – May. Seeds ripen in September. Male catkins oval, purple-red, up to 12 mm long and 6-7 mm thick.

Female cones reddish, erect or pendulous; when fully mature dark brown, ovoid-ovate in shape, 3.5-8 cm long and up to 2.5 cm in diameter.

Seed scales convex, thin, fan-shaped, rounded at the upper end, sometimes truncate, entire-margined, less often weakly emarginate. Scales brown-yellow, shiny, slightly covered with short matte pubescence.

Seed scales are a species-specific characteristic of Siberian spruce. Bract scales are five times shorter than the seed scales, coarsely toothed (as if gnawed) at the apex. Seeds small, ovoid, from almost black to pale yellow, with a wing three times longer than the seed.

Hybrids: in the northeastern part of Europe it hybridizes with Norway spruce, forming the Finnish spruce.

Varieties: known are 4 varieties: «Krylova» («krylovii Lucznik»), «Lutescens (yellowish)» («lutescens Lucznik»), «Lucifera (shining)» («lucifera Lucznik»), «Coerulea (blue)» («coerulea Tigerotedt»).

Hardiness zone: 2a (-45°)

Position/site: light-loving but shade-tolerant. In young age it suffers from spring scorch. Grows well on fresh, well-drained acidic sandy or loamy soils. Does not tolerate waterlogging, drought or soil salinity. Does not like air pollution. In monoculture it can lead to soil acidification.

Planting: Soil mix: sod and leaf soil, peat, sand in ratio 2:2:1:1. Drainage made from crushed brick, layer 15-20 cm. Planting depth: 50-70 cm. Root collar at ground level.

Care: after planting you can apply 100-150 g of nitroammophoska. During dry periods it is recommended to water daily 10-12 L per plant. Overhead (spray) watering of the crown is also desirable. Loosening is carried out to a depth of 5-6 cm; peat is not removed but mixed with the soil. Young seedlings need to be covered with boughs for the winter.

Pruning: tolerates pruning well. With proper formation of a hedge, an «impenetrable green wall» effect can be achieved. When forming two leaders, one should be removed.

Diseases: Schütte, snow Schütte, fusariosis, stem and root rot, bark necrosis, ulcerative (wound) canker, cone rust, spruce vertun.

Pests: spruce leaf-roller, spider mite, Sitka spruce aphid.

Propagation: by seeds, cuttings, grafting or layering. Lower branches root well in the soil. When propagated by seed, decorative qualities may be lost. Seed germination 60-80%. Seeds germinate without pre-sowing treatment, but soaking in water (18-22 hours) or cold stratification (2-8 weeks) increases germination percentage. In closed containers seeds can be stored up to 5 years.

Uses: uses similar to Norway spruce.