Douglas-Fir - Pseudotsuga menziesii

Family: Pinaceae - Pine Family

[IFBC-E-flora]

Habitat / Range
Moist to dry slopes, river terraces and flats in the lowland and montane zones; common in S BC, infrequent northward to C BC; E to SW AB and S to CA and MX. [IFBC-E-flora]

[E-flora]

Identification

Pseudotsuga menziesii is an evergreen Tree growing to 75 m (246ft) by 20 m (65ft) at a fast rate.
It is hardy to zone (UK) 7 and is not frost tender. It is in leaf 12-Jan It is in flower from Mar to May, and the seeds ripen from Sep to November. 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. Suitable pH: acid and neutral soils. It cannot grow in the shade. It prefers moist or wet soil. The plant can tolerates strong winds but not maritime exposure.[PFAF]

SUBTAXA PRESENT IN BC

Douglas-fir is usually separated into 2 subspecies: coastal Douglas-fir (ssp. menziesii) and interior Douglas-fir (ssp. glauca). Interior Douglas-fir, which does not occur in our region, is a smaller, stockier tree with smaller cones (to 7 cm long) and bluish-green foliage. Under natural conditions, Douglas-fir establishes primarily after fires on wetter sites, and the trees can live for over a thousand years. Thus many ancient old-growth forests contain giant Douglas-fir that represent the legacy of fires that swept the landscape many centuries ago. The trees have very thick bark, which allows them to survive moderate surface fires. · Douglas-fir is not related to the true firs (Abies spp.). [PCBC2004]

Origin Status: Native [E-flora]
General: Tree up to 70 (occasionally to 90) m tall; rounded to flattened crown when older, young trees with pyramidal crown; bark very thick, rough, dark brown. [IFBC-E-flora]
Leaves: Needles (1.5) 2-3 (3.5) cm long, spreading around twig or turned upward, obtuse to abruptly sharp-pointed tip; color varies from yellow-green to dark-green in var. menziesii to blue-green in var. glauca, lower surface with two longitudinal bands of white stomata. [IFBC-E-flora]
Cones: Seed cones drooping, yellowish- to purplish-green when young, turning reddish-brown, soon deciduous; 6-10 cm long in var. menziesii, 4-7 cm in var. glauca; scales with 3-lobed tip, the centre one the longest; pollen cones yellow to reddish, 6-10 mm long.[IFBC-E-flora]
Notes:
Two varieties are recognized in BC:
1. Cones mostly 6-10 cm long, the bracts straight and appressed toward the cone tip; leaves deep (yellowish) green; primarily coastal.................. var. menziesii (coast Douglas-fir)
1. Cones mostly 4-7 cm long, the bracts appressed to spreading or reflexed; leaves more bluish-green; primarily interior................. var. glauca (Beissn.) Franco (Rocky Mountain Douglas-fir) [IFBC-E-flora]
USDA Blooming Period: Mid Spring
USDA Fruit/Seed characteristics:

Colour: Brown
Present from Summer to Fall

[USDA-E-flora]


Edible Uses

Other Uses

Medicinal Uses

Douglas fir was often employed medicinally by various native North American Indian tribes who used it to treat a variety of complaints[257PFAF]. It is little, if at all, used in modern herbalism.[PFAF]


DOUGLAS FIR (Pseudotsuga menziesii (Mirb.) Franco.) + [HMH Duke]
Activities (Douglas Fir) — Antidote, cicuta (f; DEM); Antiseptic (f; DEM); Antitussive (f; DEM);

Diuretic (f; DEM); Emetic (f; DEM); Laxative (f; DEM); Tonic (f; DEM).

Indications (Douglas Fir) — Allergy (f; DEM); Anemia (f; DEM); Athlete’s Foot (f; DEM);

Carbuncle (f; DEM); Chest Ache (f; DEM); Cold (f; DEM); Constipation (f; DEM); Cough (f; DEM); Cystosis (f; DEM); Dermatosis (f; DEM); Diarrhea (f; DEM); Dysmenorrhea (f; DEM); Enterosis (f; DEM); Fever (f; DEM); Fungus (f; DEM); Gastrosis (f; DEM); Gonorrhea (f; DEM); Halitosis (f; DEM); Headache (f; DEM); Infection (f; DEM); Nephrosis (f; DEM); Osteosis (f; DEM); Pain (f; DEM); Paralysis (f; DEM); Rheumatism (f; DEM); Sore (f; DEM); Sore Throat (f; DEM); Stomatosis (f; DEM); VD (f; DEM); Water Retention (f; DEM).


Lore

As a charm, a hunter's bow and arrows would be passed through the smoke from Douglas-Fir boughs placed on the fire while an incantation was sung. This was supposed to keep the deer from scenting the hunter and to secure success to the hunt. Soot gathered from burning the gum in a hollow tree was rubbed into the punctures of the three parallel lines of the tattoo marking a girls chin. [EuCp. p. 67-69]

Phytochemicals

Neolignan Glycosides
The methanol extract of the outer bark;

[NGPS]

In previous research on the methanol extracts of the inner and outer bark of this tree (voucher specimen number 173773 de- posited at the Oregon State University Herbarium) the pre- sence of flavonoid glycosides, procyanidins, phlobaphenes, and related oxidatively coupled compounds has been reported (3, 4).[NGPM]

First Nations Use
Douglas fir is perhaps the most abundant tree species in the Coast Salish territory. Everywhere the bark was considered to be a top quality fuel because it burned with a hot smokeless flame. Though not as valuable as cedar or yew, the wood was used to make spoons, seal harpoon shafts, fire tongs, and other articles (Barnett, 1955). Fir knots were molded into curved halibut and cod hooks by steaming them, placing them in a hollow kelp stem overnight, and bending them to the right shape. The finished hook was often rubbed with tallow to keep its shape. Barnett also mentions the use of rotten fir wood to tan hides and of fir branches and poles to weave salmon weirs. The pitch was used to patch canoes or water vessels (op. cit.).[Turner&Bell]
The wood was used for making coffins, and probably other articles also (Dawson, 1887). The thick bark from old trees was prized as a fuel (King, 1972). Young fir bark, burned, pulverized, and mixed with water in which ...[Cicuta douglasii] had been rubbed, was taken for diarrhoea (Boas, 1966). When a man had a carbuncle, his younger brother mixed Douglas Fir bark with perch oil and eagle down on a skunk cabbage leaf (Lysichiturn americanum) and applied it to the sore. It was held on with a cedar bark pad for three days, and then the carbuncle was cut open (Boas, 1930). The pitch was also a good medicine (Cranmer, 1969). In mythology, the Cannibal woman used Douglas Fir pitch to seal the eyes of the children she was stealing so they would not be able to see where they were going (Boas, 1910).[Turner&Bell]
Smoke The Thompson of British Columbia, Canada, gathered the rotten wood of this species and burned it to smoke cure their animal hides (Turner et al. 1990).[UAPDS]


Cultivation

Prefers a moist but not water-logged alluvial soil[1]. Dislikes calcareous soils[1]. Trees are a failure on dry hungry soils.[11]. Whilst they are moderately wind resistant[166], tall specimens are likely to lose their crowns once they are more than 30 metres tall in all but the most sheltered areas[185]. A very ornamental tree[1], it is the most cultivated timber tree in the world and is extensively used for re-afforestation in Britain[200]. There are several named varieties selected for their ornamental value[188]. Trees can be established in light shade but this must be removed in the first few years or growth will suffer[185]. Very slow growing for its first few years, growth soon becomes extremely fast with new shoots of up to 1.2 metres a year[185]. This annual increase can be maintained for many years[185]. Trees in sheltered Scottish valleys have reached 55 metres in 100 years[200]. New growth takes place from May to July[185]. The trees require abundant rainfall for good growth[11, 49]. 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[200]. Trees are very long-lived, specimens over 1,000 years old are known[226]. Seed production commences when trees are about 10 years old, though good production takes another 15 - 20 years[229]. Good crops are produced about every 6 years[229]. This tree is a pioneer species because it cannot reproduce under its own canopy[226]. The bark on mature trees can be 30cm thick, and this insulates the trunks from the heat of forest fires[213]. This species is notably resistant to honey fungus[81, 200]. Young growth can be damaged by late frosts[81]. The leaves have a strong sweet fruity aroma[185]. Special Features: North American native, Inconspicuous flowers or blooms.[PFAF]

Shelterbelt: A fast growing and fairly wind-resistant tree, it is often used in shelterbelt plantings[185PFAF].

Establishment
Adaptation: Douglas-fir needs excellent drainage. In the higher elevations of the West that receive snow and in the lower foothills that have moderately cold winters and hot summers, Douglas-fir requires moderate summer watering, generally 1-4 times per month depending upon the absorption rate and water retention capacity of the soil. It does best in full or part-shade and may tolerate morning and winter sun in ocean-influenced areas of northern and central California.
If establishing the tree by seed, remove the seeds from the cones, gently rub the wings off, and soak them in water for 24 hours, drain them, and thoroughly surface-dry them. Put them in a plastic bag, without any medium, seal the bag and place them in refrigerated conditions until their chilling treatment begins. Allow three times the air space as seed space in the bag. It is best to sow the seeds in late February to early March. Expose the seeds to a chilling treatment of at least four weeks prior to sowing.[USDA1]
Bears may feed on new sapwood and inner bark in the spring and early summer.
Erosion Control and Windbreaks: Although it is seldom used, Douglas-fir is an excellent tree for windbreaks on adapted soils. It is also excellent for restoring eroded lands, watersheds, and strip-mined areas.
Recreation: It is an excellent tree for recreation purposes. It is windfirm on all but the wet and very shallow soils and is generally quite free from the killing attacks of insects and disease in park conditions. There is a good response to properly applied pruning, shearing, and thinning. Pruning: Trees prune well and heal over quickly if the stands are young and less than 10 inches in diameter.
Several insects attack Douglas-fir, but the Douglas-fir beetle is the most important. Outbreaks usually occur in windthrown, fire-killed or felled timber. Timber in any of the conditions listed should be removed as quickly as possible. Periodic outbreaks of Douglas-fir tussock moths may cause serious damage. [USDA1]

Propagation
Seed - best sown in the autumn to winter in a cold frame so that it is stratified[80]. 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[80]. If you have plenty of seed then it can be sown in an outdoor seedbed in early spring[80]. Grow the plants on for at least two years in the seedbed before planting them out in late autumn or early spring.[PFAF]


Synonyms
Pseudotsuga mucronata (Raf.) Sudw. [E-flora]
P. douglasii. P. mucronata. P. taxifolia. Abies douglasii. A. taxifolia. Pinus taxifolia.[PFAF]


References

  1. [E-flora] http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Pseudotsuga%20menziesii&redblue=Both&lifeform=1 [Accessed: 11/26/2014 6:59:07 PM ]
  2. [NGPM] Neolignan Glycosides from Pseudotsuga menziesii, Rubén F. González-Laredo, Joseph J. Karchesy, Planta Med 1996; 62(6)
  3. [PFAF] http://www.pfaf.org/user/Plant.aspx?LatinName=Pseudotsuga+menziesii, Accessed Jan 13, 2015
  4. [USDA1]Douglas-Fir Pseudotsuga menziesii, USDA Plant Guide, M. Kat Anderson USDA, NRCS, National Plant Data Center, Department of Plant Sciences, University of California, Davis, California

Page last modified on Friday, April 13, 2018 12:05 PM