Herbs & Plants

Picea glauca

Botanical Name : Picea glauca
Family: Pinaceae
Genus: Picea
Species: P. glauca
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales

Synonyms : Picea alba.
Common Names: White spruce. It is also known as Canadian spruce, skunk spruce, cat spruce, Black Hills spruce, western white spruce, Alberta white spruce, and Porsild spruce.
Habitat : Picea glauca is native to the northern temperate and boreal forests in North America. Picea glauca was originally native from central Alaska all the east across southern/central Canada to the Avalon Peninsula in Newfoundland. It now has become naturalized southward into the far northern USA border states like Montana, Minnesota, Wisconsin, Michigan, Vermont, New Hampshire, and Maine; there is also an isolated population in the Black Hills of South Dakota and Wyoming. It grows in woods in good soils. Along streams and lakes and also on rocky hills and slopes, succeeding in a variety of soil conditions.
Picea glauca is a large coniferous evergreen tree which grows normally to 15 to 30 metres (49 to 98 ft) tall, but can grow up to 40 m (130 ft) tall with a trunk diameter of up to 1 m (3.3 ft). The bark is thin and scaly, flaking off in small circular plates 5 to 10 centimetres (2.0 to 3.9 in) across. The crown is narrow – conic in young trees, becoming cylindric in older trees. The shoots are pale buff-brown, glabrous (hairless) in the east of the range, but often pubescent in the west, and with prominent pulvini. The leaves are needle-like, 12 to 20 millimetres (0.47 to 0.79 in) long, rhombic in cross-section, glaucous blue-green above with several thin lines of stomata, and blue-white below with two broad bands of stomata.

The cones are pendulous, slender, cylindrical, 3 to 7 cm (1.2 to 2.8 in) long and 1.5 cm (0.59 in) wide when closed, opening to 2.5 cm (0.98 in) broad. They have thin, flexible scales 15 mm (0.59 in) long, with a smoothly rounded margin. They are green or reddish, maturing to pale brown 4 to 8 months after pollination. The seeds are black, 2 to 3 mm (0.079 to 0.118 in) long, with a slender, 5 to 8 mm (0.20 to 0.31 in) long pale brown wing.


Bloom Color is Red, Yellow. Main Blooming time is early spring, late spring, mid spring and the form is columnar, pyramidal.

It is in leaf 12-Jan, and the seeds ripen in September. The flowers are monoecious (individual flowers are either male or female, but both sexes can be found on the same plant) and are pollinated by Wind.Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay and nutritionally poor soils. Suitable pH: acid and neutral soils and can grow in very acid soils.
It cannot grow in the shade. It prefers moist or wet soil. The plant can tolerates strong winds but not maritime exposure.
It cannot tolerate atmospheric pollution.
Likes abundant moisture at the roots, if grown in drier areas it must be given a deep moist soil. Tolerates poor peaty soils. Succeeds in wet cold and shallow soils but is not very wind-firm in shallow soils. Prefers a pH between 4 to 6. Dislikes shade. Intolerant of atmospheric pollution. Resists wind exposure to some degree. A fast growing tree, especially when young with annual increases of up to 1 metre in height. New growth takes place from April to July. Growth slows considerably as the trees grow older. It is an important forestry tree in N. America and is also planted for timber in N. Europe. It is sometimes used as a ‘Christmas tree’, but is unsuited for this because its leaves quickly fall. Seed production begins at approximately 20 years, though reliable crops make take twice that long. Heavy crops are produced every 2 – 5 years. Trees should be planted into their permanent positions when they are quite small, between 30 and 90cm. Larger trees will check badly and hardly put on any growth for several years. This also badly affects root development and wind resistance. In some upland areas, especially over granitic or other base-poor soils, growth rate and health have been seriously affected by aluminium poisoning induced by acid rain. Plants are strongly outbreeding, self-fertilized seed usually grows poorly[200]. They hybridize freely with other members of this genus. There are some named varieties selected for their ornamental value[200]. The crushed leaves are quite aromatic. Some people find the smell distasteful saying that it is like skunks, whilst others say it has a pleasant smell like blackcurrants or mouldy grapefruit. Special Features:North American native, Inconspicuous flowers or blooms.

Seed – stratification will probably improve germination so sow fresh seed in the autumn in a cold frame if possible. Sow stored seed as early in the year as possible in a cold frame. A position in light shade is probably best. Seed should not be allowed to dry out and should be stored in a cool place. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse or cold frame for their first winter. They can be planted out into their permanent positions in early summer of the following year, or be placed in an outdoor nursery bed for a year or so to increase in size. They might need protection from spring frosts. Cuttings of semi-ripe terminal shoots, 5 – 8cm long, August in a frame. Protect from frost. Forms roots in the spring. Cuttings of mature terminal shoots, 5 – 10cm long, September/October in a cold frame. Takes 12 months. Cuttings of soft to semi-ripe wood, early summer in a frame. Slow but sure.

Edible Uses:
Edible Parts: Flowers; Inner bark; Seed; Seedpod.

Young male catkins – raw or cooked. Used as a flavouring. Immature female cones – cooked. The central portion, when roasted, is sweet and syrupy. The cones are about 5cm long. Inner bark – raw or cooked. It can be dried, ground into a powder and then used as a thickener in soups etc or added to cereals when making bread. Usually harvested in the spring, it is an emergency food that is only used when all else fails. Seed – raw. The seed is about 2 – 4mm long and is too small and fiddly to be worthwhile unless you are desperate. A refreshing tea, rich in vitamin C, can be made from the young shoot tips. The trunk yields a gum, used for chewing. Spruce oil, distilled from the leaves and twigs, is used in the food industry to flavour chewing gum, ice cream, soft drinks and sweets.
Medicinal Uses:
White spruce was widely employed medicinally by several native North American Indian tribes, who valued it especially for treating chest complaints. It is little, if at all, used in modern herbalism. An infusion of the cones has been used in the treatment of urinary troubles. The inner bark is pectoral. It has been chewed, and an infusion drunk, in the treatment of TB, influenza, coughs and colds. An infusion is also drunk in the treatment of rheumatism. The inner bark has also been used as a poultice on sores and infected areas, and has also been used to bandage cuts. The tea made from the young shoot tips has antiseptic properties. It is used in the treatment of respiratory infections. A decoction of the stems is used as a herbal steam bath in the treatment of rheumatism. The gum is antiseptic, digestive, laxative, pectoral and salve. A decoction has been used in the treatment of respiratory complaints. The gum obtained from the trunk (probably pitch) has been used as a salve on sores and cuts. A poultice of the gum mixed with oil has been used to treat skin rashes, scabies, persistent scabs, growing boils etc, and has also been used on wounds where there is blood poisoning. The rotten, dried, finely powdered wood has been used as a baby powder and as a treatment for skin rashes.

Other Uses:
Baby care; Dye; Gum; Musical; Pitch; Repellent; Shelterbelt; String; Tannin; Waterproofing; Wood.

A fairly wind resistant tree, it can be grown as part of a shelterbelt planting. The cultivar ‘Denstat’ has been recommended[200]. The leaves have been burnt to repel insects. Various native North American Indian tribes made a string from the long roots of this species and used it to stitch the bark of their canoes and to make baskets etc. The rotten, dried, finely powdered wood has been used as a baby powder and as a treatment for skin rashes. The bark is a source of tannin. A yellow-brown dye can be obtained from the rotten wood. The pitch obtained from the trunk can be used as a waterproofing sealant in canoes. Wood – straight-grained, resilient, light, soft, not strong. Used for construction and as a source of pulp for paper making. The resonance of the wood, and its capacity to transmit vibrations, make it an ideal wood for guitars, violins, piano soundboards etc

Landscape Uses:Christmas tree, Firewood, Screen, Specimen.

White spruce is the provincial tree of Manitoba and the state tree of South Dakota.

Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.