Abies sibirica Seeds | Siberian Fir
LATIN NAME: Abies sibirica
COMMON NAME: Siberian Fir
Plant Profile
The Siberian fir is a slender tree of the dark northern forest, reaching 25 to 30 metres with a narrow, sharply tapering, spire-like crown. It grows in pure stands and in mixture with Siberian spruce, larch and stone pine, and it is one of the most cold-hardy trees in the north. The bark is smooth pale grey and studded with resin blisters, the vesicles found in the bark of true firs and in no other conifer genus.
The needles are flattened, dark green and glossy above, 2 to 3 cm long, with two bright white stomatal bands beneath and a notched tip, arranged spirally but twisted at the base so they lie in two flat ranks. Pull a dead needle away and the twig shows a small circular leaf scar flush with the bark, not the raised woody peg a spruce leaves behind.
Fir cones sit upright on the branchlets and never hang, and they are dismembered rather than dropped. As a cone ripens, the scales detach from the central axis one by one and release the winged seeds, leaving the bare spike of the rachis on the tree. The cones here are cylindrical, violet-purple to greenish before they dry, and they are produced heavily in mast years with light crops between.
Fir seed is short-lived in storage and the seedlings resent disturbance.
Lift the seedlings with a ball of soil when they are 5 to 8 cm tall, pot them into deep containers and grow them on in light shade. Firs have a shallow, fibrous root system and hate to be bare-rooted, so plant out at 25 to 30 cm in a moist but well-drained site, mulch to keep the roots cool. Watch for the adelgids that distort fir shoots, and for deer, which will take the leader out of a young tree.
Science & Biotechnology
Bornyl acetate is more than a fragrance. Hydrolyse the ester and you get borneol, the crystalline alcohol with the camphor-like smell, and oxidise borneol and you reach camphor, which is one of the routes by which the camphor of commerce has been made. The terpene synthases that assemble these skeletons from geranyl diphosphate are among the best studied enzymes in conifer biochemistry.
Uses & Benefits
Where a fir forest is cut, the standing value of the tree is measured in cubic metres of softwood. The value of the branches is measured in the still.
Fir needle oil from this species is dominated by bornyl acetate, with camphene, pinene, limonene, santene and borneol completing the profile. In the Russian north the oil has long been recovered by steam distillation of the leafy branches left after felling, a forest-industry process rather than a cottage craft.
Puncture a resin blister and a clear sticky oleoresin runs out. In the firs this balsam is tapped where a transparent, slowly hardening resin is wanted, and the best-known member of the family in trade is Canada balsam from the North American balsam fir, long used as a mounting medium for microscope slides and as a fixative in perfumery.
Fir wood is light, soft and pale beside pine, useful for pulping and cheap for construction but weak in the weather.
Siberian fir supplies pulpwood, boxwood for crates and packing, and general construction timber where it grows, though untreated it rots quickly out of doors. The taiga stands also protect the soil, hold snow and regulate runoff over enormous catchments.
Fir needle oil carries a bracing, green, resinous note with a sweet camphoraceous back, and it is used in soaps, detergents and air-care products. In the garden the tree is grown for the shape and the smell of the foliage rather than for the oil.
Growing from Seed
Sow as soon as the seed is ripe, or store it cool and moist rather than dry and warm, because fir seed loses its power to sprout in a warm room. Fill a deep pot with a gritty, humus-rich, lime-free mix, press the seed onto the surface and cover it with 5 mm of fine compost, then keep the frame shaded and never let it dry out.
Our Take
Siberian fir suits a gardener with room for something narrow and severe at the back of the plot. Plant it beside the smaller, blue-coned Veitch’s fir if you want a collection, or against the dense dark screen that a Nordmann fir eventually makes. For a faster northern conifer in the same climate, Siberian larch is the obvious companion and turns gold before either. Give the tree a cool root run and keep the mower away from the trunk.
Related Reading
More species in the same orbit as Siberian Fir: