The entries in this record refer specifically to Pseudotsuga menziesii var glauca, which is sometimes recognised as a distinct species (as Pseudotsuga lindleyana). A separate record exists for Pseudotsuga menziesii var menziesii.

Common Name: Rocky Mountain Douglas Fir

General Information

Pseudotsuga menziesii glauca is an evergreen tree with a slender, conical crown that is usually fairly thin and sparsely foliaged; it commonly grows 25 - 30 metres tall, occasionally reaching 40 - 50 metres. The straight, cylindrical bole is usually 40 - 80cm in diameter, occasionally to 125 - 200cm[, ].
The tree is widely harvested for its wood and also has a wide variety of traditional uses as a food, medicine and source of materials[].

Known Hazards

None known

Botanical References

,

Range

Western N. America - British Colombia and Alberta, southwards mainly on the eastern side of the Rockies to Arizona and Texas and to southern Mexico.

Habitat

Coniferous or mixed forests; at elevations from 600 - 3,000 metres in the USA[]. Mixed mesophytic forest at medium to high elevations; at elevations from 2,300 - 3,300 metres in Mexico[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	25.00 m
Growth Rate	Medium
Pollinators	Wind
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Pseudotsuga menziesii glauca occurs in a huge area from north to south in western North America, from British Colombia to southern Mexico, growing further inland than Pseudotsuga menziesii. It occupies a variety of climatic zones, landscapes and habitats at elevations from as low as 600 metres in the north of its range up to 3,300 metres in the south[]
Prefers a moist but not water-logged alluvial soil[]. Dislikes calcareous soils[]. Trees are a failure on dry hungry soils.[]. Whilst they are moderately wind resistant[], tall specimens are likely to lose their crowns once they are more than 30 metres tall in all but the most sheltered areas[].
A very ornamental tree[], it is the most cultivated timber tree in the world and is extensively used for re-afforestation in Britain[]. There are several named varieties selected for their ornamental value[].
Trees can be established in light shade but this must be removed in the first few years or growth will suffer[].
Very slow growing for its first few years, growth soon becomes moderately fast []. New growth takes place from May to July[]. The trees require abundant rainfall for good growth[, ].
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[].
Trees are very long-lived, specimens over 1,000 years old are known[]. Seed production commences when trees are about 10 years old, though good production takes another 15 - 20 years[]. Good crops are produced about every 6 years[].
This tree is a pioneer species because it cannot reproduce under its own canopy[].
The bark on mature trees can be 30cm thick, and this insulates the trunks from the heat of forest fires[].
This species is notably resistant to honey fungus[, ]. Young growth can be damaged by late frosts[].
The leaves have a strong sweet fruity aroma[].

Edible Uses

Young shoot tips - used as a flavouring in cooked foods[, ]. A subtle woodsy flavour[].

A refreshing tea is made from the young leaves and twigs[, , , ]. Rich in vitamin C[]. It is used as a coffee substitute according to some reports[, , , ]. The fresh leaves have a pleasant balsamic odour and are used as a coffee substitute[].

Inner bark - dried, ground into a meal and mixed with cereals for making bread etc[, ]. A famine food used when all else fails[].

A sweet manna-like substance is exuded from the bark[, ]. This report possibly refers to the resin that is obtained from the trunk[], and is used as a chewing gum by various native North American Indian tribes[]. Alternatively, the report could be referring to the sap which is used as a sugar-like food[].

Medicinal

This species was often employed medicinally by various native North American Indian tribes who used it to treat a variety of complaints[]. It is little, if at all, used in modern herbalism.

An antiseptic resin is obtained from the trunk. It is used as a poultice to treat cuts, burns, wounds and other skin ailments[, ]. The poultice is also used to treat injured or dislocated bones[]. The resin is used in the treatment of coughs and can be chewed as a treatment for sore throats[].

An infusion of the green bark has been used in the treatment of excessive menstruation, bleeding bowels and stomach problems[].

An infusion of the leaves has been used as a wash and a sweat bath for rheumatic and paralyzed joints[].

An infusion of the young sprouts has been used in the treatment of colds[].

An infusion of the twigs or shoots has been used in the treatment of kidney and bladder problems[].

A decoction of the buds has been used in the treatment of venereal disease[].

Young shoots have been placed in the tips of shoes to keep the feet from perspiring and to prevent athletes foot[].
A mouthwash is made by soaking the shoots in cold water[].

Other Uses

A light brown dye is obtained from the bark[, ].

The bark is a source of tannins[, ].

The bark can be used as a cork substitute[] and is also used to make fertilizer[].

The small roots have been used to make baskets[].

The plant has insecticidal properties[].

A resin is obtained from the trunk, similar to Abies balsamea[, ] which is used in the manufacture of glues, candles, as a cement for microscopes and slides and also as a fixative in soaps and perfumery[]. The resin can also be used as a caulking material on boats[].

The wood is heavy, strong, fine grained, durable, though it can be of variable quality. It dries quickly, does not warp and is easily worked, it is used for heavy construction, telegraph poles, furniture etc[, , , , , , , ]. This variety grows much slower than the species and to a more moderate size. It yields a denser, heavier wood which is excellent for cooperage for vats and tanks for breweries and distilleries[].
The wood is a good quality fuel[, , ].
The bark contains pitch, it burns with a lot of heat and almost no smoke, so it is prized as a fuel[, ].

Propagation

Seed - best sown in the autumn to winter in a cold frame so that it is stratified[]. The seed can also be stored dry and sown in late winter. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in light shade in the cold frame for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Seedlings tolerate light shade for their first few years of growth. Cones often fall from the tree with their seed still inside[].
If you have plenty of seed then it can be sown in an outdoor seedbed in early spring[]. Grow the plants on for at least two years in the seedbed before planting them out in late autumn or early spring.