Picea pungens

Blue Spruce

a perennial woody evergreen member of the Picea genus in the family Pinaceae.

No photo available

Taxonomy and growth

Family
Pinaceae
Genus
Picea
Life cycle
perennial
Foliage
evergreen
Woodiness
woody
Growth rate
moderate
Height
20 m
Spread
5 m
Fertility
Wind
Flower type
monoecious
Pollinators
Wind

Uses

Edible uses

This section contains historical Plants For A Future notes marked noncommercial.

Young male catkins - raw or cooked. Used as a flavouring[4]. Immature female cones - cooked. The central portion, when roasted, is sweet and syrupy[4]. The cones are about 7cm long[14]. Inner bark - dried, ground into a powder and then used as a thickener in soups etc or added to cereals when making bread[4]. An emergency food, it is only used when all else fails. Seed - raw[4]. The seed is about 2 - 4mm long[9]. It is rich in fats and has a pleasant slightly resinous flavour but is too small and fiddly to be worthwhile unless you are desperate[172, K]. A refreshing tea, rich in vitamin C, can be made from the young shoot tips[4].

Plant part
Flowers
Plant part
Inner bark
Plant part
Seed
Product or use
Tea

Material uses

This section contains historical Plants For A Future notes marked noncommercial.

A fairly wind resistant tree, it can be grown as part of a shelterbelt planting[7]. Wood - light, soft, close grained, weak, brittle and often full of knots[14][3][9]. The wood has little commercial value[8], but is used for construction[14] and is also valued for its use in the pulp industry to make paper[3].

Product or use
Wood

Ecology and functions

Ecosystem niche
Canopy

Windbreak

Environment

Range
South-western N. America - Rocky Mountains.
Habitat
Banks of streams or on first benches above them, singly or in small groves, 2000 - 3300 metres[14].
Light
full sun
Shade tolerance
no shade
Water
moderate
Hardiness
Zone 3+
Soil textures
sandy, loamy, clay
Soil pH
very acid, acid, neutral
Tolerances
high wind
Wind
Yes
Tolerates Nutritionally Poor Soil
No
Drought
intolerant

Propagation

This section contains historical Plants For A Future notes marked noncommercial.

Seed - stratification will probably improve germination so sow fresh seed in the autumn in a cold frame if possible[13]. Sow stored seed as early in the year as possible in a cold frame[12]. A position in light shade is probably best[12]. Seed should not be allowed to dry out and should be stored in a cool place[13]. 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[12]. Cuttings of mature terminal shoots, 5 - 10cm long, September/October in a cold frame. Takes 12 months[12]. Cuttings of soft to semi-ripe wood, early summer in a frame. Slow but sure.

Cultivation

This section contains historical Plants For A Future notes marked noncommercial.

Likes abundant moisture at the roots, if grown in drier areas it must be given a deep moist soil[2]. Tolerates poor peaty soils[7]. Prefers a cold dry high mountain site[7]. Succeeds in wet cold and shallow soils but is not very wind-firm in shallow soils[1]. Resists wind exposure to some degree[7]. This species has a deeply penetrating root system that firmly anchors the tree against winds[9]. Prefers a pH between 4 to 6[7]. Dislikes shade[7]. Intolerant of atmospheric pollution[2]. A long-lived but slow-growing tree in the wild, with specimens 800 years old recorded[9]. It is planted as a timber tree in N. and C. Europe[11]. Most trees in Britain are grafted and these are slow growing[5]. The few trees of seedling origin tend to be fairly fast growing after a slow start[5]. Annual increases of 30 - 40cm are not uncommon in some of the larger trees. 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[7]. Seed production is usually good, with heavy crops every 2 - 3 years[9]. 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[7]. Plants are strongly outbreeding, self-fertilized seed usually grows poorly[7]. They hybridize freely with other members of this genus[7]. There are several named forms, selected for their ornamental value[6]. Trees are very subject to severe damage by aphids in mild winter areas where temperatures do not regularly fall below -8°c[7]. All parts of the plant emit a powerful pungent smell when bruised[10].

References

  1. F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951-00-00

  2. Bean. W. Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. Murray 1981-00-00

  3. Hill. A. F. Economic Botany. The Maple Press 1952-00-00

  4. Schofield. J. J. Discovering Wild Plants - Alaska, W. Canada and the Northwest.

  5. Mitchell. A. F. Conifers in the British Isles. HMSO 1975-00-00 ISBN 0-11-710012-9

  6. Brickell. C. The RHS Gardener's Encyclopedia of Plants and Flowers Dorling Kindersley Publishers Ltd. 1990-00-00 ISBN 0-86318-386-7

  7. Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5

  8. Lauriault. J. Identification Guide to the Trees of Canada Fitzhenry and Whiteside, Ontario. 1989-00-00 ISBN 0889025649

  9. Elias. T. The Complete Trees of N. America. Field Guide and Natural History. Van Nostrand Reinhold Co. 1980-00-00 ISBN 0442238622

  10. Genders. R. Scented Flora of the World. Robert Hale. London. 1994-00-00 ISBN 0-7090-5440-8

  11. ? Flora Europaea Cambridge University Press 1964-00-00

  12. Sheat. W. G. Propagation of Trees, Shrubs and Conifers. MacMillan and Co 1948-00-00

  13. McMillan-Browse. P. Hardy Woody Plants from Seed. Grower Books 1985-00-00 ISBN 0-901361-21-6

  14. Sargent. C. S. Manual of the Trees of N. America. Dover Publications Inc. New York. 1965-00-00 ISBN 0-486-20278-X

Edit this page