Monday, March 3, 2014
Douglas Fir
Rumored to be as high as 443 feet and more( pre 1900 )
British Columbia, Canada - 424 feet ( felled on 1895 )
Lynn Valley, B.C., Canada- 415 feet - 1902
Mineral, WA 393 feet - 1905
Nisqually River, WA 380 feet - 1899
Recommended video found on Youtube ( rating 10 / 10 )
One of the worlds tallest trees, and in fact 2 Douglas Firs recorded in Washington State and British Columbia, Canada are likely the tallest trees to have ever grown in North America. While these extreme giants no longer exist, trees over 300 feet still grow in Cathedral Grove on Vancouver, B.C., Canada and my hike through the dark, dampened, mossy forest on a rainy August day staring up at the towering canopies in awe permanently cemented my passion for trees, conservation and horticulture. The driving rain in the canopies that give the coastal rainforest their name filtered down to a gently rain on the forest floor which was serenely silent yet felt like it was exuding life from every pore.
The Douglas Fir thrives in many places around the world and is even planted as a lumber tree in the British Isles where it grows every bit as fast and my someday grow as large as in the Pacific rainforest I describe above. It is native to western North America from British Columbia south to California and east to cover most of the Rocky Mountains and forms great forests over much of that region. It can easily exceed 200 feet in wet climates or grow to less than 100 feet in drier regions. Some records include: fastest recorded growth rate - 7 feet; 5 years - 17 feet; 20 years - 120 x 23 feet; 70 years - 166 feet; 90 years - trunk diameter of 4 feet; 115 years - trunk diameter of 6 feet; 123 years - 210 feet ( England ); 180 years - trunk diameter of 10 feet ( England ); largest on record - 400 ( 329 confirmed modern ) x 19 foot trunk diameter; tallest in Scotland - 213 feet; largest in Connecticut - 110 feet; largest in Maryland - 95 x 45 feet.
Young trees are conical though become more columnar and often flat topped with age. The branches are plume-like and the branchlets droop.
The Douglas Fir has been recorded living as long as 1400 years.
A major lumber tree and economic driver, the Douglas Firs timber is used to telephone poles, plywood and wood pulp.
The narrow leaves grow radially from the shoots and are deep blue-green above and have 2 white bands beneath. The new foliage in spring is a fresh bright green.
The linear leaves, up to 2 inches in length last up to 8 years.
The distinctive, hanging cones are green turning to red-brown and up to 4 or rarely 5 inches in length.
The thick, red-brown bark has deep fissures and corky plates.
The wood is light yet strong.
Typically hardiness depends upon seed source but may be from zone 4 to 8 tolerating as low as -32 F.
All species of Pseudotsuga prefer full sun on just about any well drained soil.
Propagation is from seed in spring though cultivars can be grafted in late winter.
Young trees should be pruned in March and is usually restricted to maintaining a single leader in young trees or removing lower branches for clearance as the tree grows.
* photo taken by A. Gaskill @ USDA-NRCS PLANTS Database
* photo taken by G.E. Griffith @ USDA-NRCS PLANTS Database
* USDA-NRCS PLANTS Database
* photo taken by K.D. Swan @ USDA-NRCS PLANTS Database
* photo taken on August 1991 outside Vancouver, B.C.
* photo of unknown internet source
* videos found on Youtube
Fastigiata
Columnar habit. Largest on record - 130 feet with a trunk diameter of 4.5 feet.
* photo taken on 4th of July 2010 @ U.S. National Arboretum, D.C.
Densa
A miniature form, reaching a maximum size of to 5 x 8 feet. Some records include: 10 years - 1 x 1.5 feet.
Fletcheri
A slow growing, attractive, irregular shaped, flat-topped bush, reaching up to 4 x 4 feet in 10 years and an eventual maximum size of 10 x 13 feet.
The foliage is soft and blue-green.
Fretsii
A slow growing, wide conical small tree reaching a maximum size of 25 x 12 feet with ascending branches that twist.
Some records include: 10 years - 6 x 4 feet; largest on record - 72 feet with a trunk diameter of 2 feet.
The aromatic, linear foliage is dull dark green.
Hardy zones 4 to 7
subsp Glauca ( Blue or Rocky Mountain Douglas Fir )
A population of the Douglas Fir native to the Rocky Mountains rather than the Pacific Coast. It does not grow quite as large, however is still massively huge when grown on ideal sites. Some records include: fastest recorded growth rate - 3 feet; 20 years - 50 x 10 ( rarely over 37 ) feet; largest on record - 200 x 65 feet with a trunk diameter of 8.5 feet. It grows dense with glaucous blue foliage and smaller cones. It is broader in habit than the coastal Douglas Fir.
It is also hardier from zones 3 to 7. One clone was reported growing in the severe zone 2 climate of Dropmore, Alberta and has even been reported to tolerate -62 F.
Prefers soil PH from 6 to 7. It is more lime tolerant than coastal forms of Douglas Fir but does not enjoy shallow, alkaline soil.
* photos taken on August 5 2010 @ Woodlands Arboretum, Clinton, Ontario
USDA-NRCS PLANTS Database / Herman, D.E., et al. 1996. North Dakota tree handbook
Glauca Pendula
A small tree, with a strong central leader and very pendulous side branches.
Some records include: 10 years - 10 x 3 feet: largest on record is 37 feet in height with a trunk diameter of 1.5 feet.
The foliage is powdery blue. It is a most spectacular landscape plant.
Oudemansii
A small broadly conical tree reaching a maximum size of 25 x 13 feet with ascending branches. It is very slow growing and its linear foliage is aromatic, shiny deep green above and light green below. Hardy zones 4 to 7.
DOUGLAS FIR RELATIVES
Pseudotsuga forrestii ( Yunnan Douglas Fir )
A large coniferous tree native to Yunnan province in China where it is endangered. Some records include: 13 years - 20 feet with a trunk diameter of 4.5 inches; largest on record - 133 x 50 feet with a trunk diameter of 3 feet.
The leaves are narrow and luxuriant green above with 2 white bands on the undersides.
The cones are conical and pendulous.
Hardy zones 6 to 9
Pseudotsuga gaussenii ( Gaussen Douglas Fir )
An extremely rare, moderate growing, large tree native to Anhui Province in China, that is related to Pseudotsuga brevifolia . Some records include: 10 years - 12 x 8 feet; largest on record - 133 x 65 feet with a trunk diameter of 3.5 feet.
Hardy zones 5 to 8 ( estimate - hasnt been fully tested north of 7 ).
Pseudotsuga guinieri
Native to mountains of Mexico and very similar to Pseudotsuga menziesii though likely will not grow nearly as tall even if planted in the ideal climate. It is also less hardy in cold climates, only surviving in zone 8 and 9
Pseudotsuga japonica
A large tree native to Japan where it is endangered. It can reach a maximum size of 135 feet with a trunk diameter of 6 feet.
The linear leaves are up to an inch in length.
Hardy north to zone 6
Pseudotsuga longibracta
A rare tree native to southern China that can reach a maximum height of 120 feet.
The linear leaves are deep green and up to an inch in length.
Hardy north to zone 8
Pseudotsuga macrocarpa ( Bigcone Douglas Fir )
A very large, fast growing tree with a broad, dense pyramidal crown and branches that are gently arching. This tree native to the mountains of southern California where rare, can reach over 150 feet.
Some records include: fastest recorded growth rate - 2.5 feet; 20 years - 50 feet; largest on record - 200 x 85 feet with a trunk diameter of 8 feet. The Bigcone Douglas Fir can live up to 700 years and is strong wooded.
The leaves are narrow and luxuriant glossy green above and gray-white below. They are up to 3 inches in length.
The cones, up to 6 or rarely 8 inches in length, are gray-brown, later ripening to light brown but are only produced on older trees.
The bark is red-brown.
Hardy zones 6 to 9 tolerating as low as -13 F though the roots are only hardy to 10 F so that young trees in colder climates should be kept mulched in winter. Extremely drought tolerant but prefers a soil PH from 5 to 7
* photo taken by R.S. Hosmer @ USDA-NRCS PLANTS Database
Pseudotsuga sinensis ( Chinese Douglas Fir )
A rare, fast growing tree native to Hunan province in western China that can reach a maximum height of 180 feet with a trunk diameter of 7 feet. Some records include: 10 years - 12 x 8 feet ( average ).
The linear leaves, up to 1.5 inches in length, are deep green.
The shoots are reddish-brown.
The thickly scaly bark is gray.
The timber is valuable for construction and making furniture.
Hardy zones 5 to 9 ( still needs more testing since some seed source get winter damage even in zone 7a ); it is very tolerant of hot humid summers
and even thrives in central Florida.
Pseudotsuga wilsonii ( Wilsons Douglas Fir )
A fast growing, large coniferous tree native to western China where it is endangered. Some records include: fastest recorded growth rate - 3 feet; 10 years - 14 x 8 feet ( average ); largest on record - 135 feet with a trunk diameter of 6.5 feet.
The needles are up to 2 inches in length. The luxuriant foliage is bright green at first, later turning deep green.
Hardy zones 7 to 9 ( unconfirmed reports of 5 & 6 ). Very tolerant of hot humid summers, it is known to thrive in the Carolinas.
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