False Hemlocks | Pseudotsuga

False Hemlocks | Pseudotsuga

Description
Description

False hemlocks, scientifically known as Pseudotsuga, are a genus of coniferous trees closely related to true hemlocks (Tsuga) but distinct in several key aspects. Known commonly as Douglas firs, they are native to North America and parts of Asia, flourishing in various habitats, from mountain slopes to coastal regions. Despite their name, they are not true firs (genus Abies) either. These trees have a long evolutionary history, with fossil records indicating their presence since the Miocene epoch.

Pseudotsuga species are characterized by their tall, straight growth, conical shape, and distinctive cones with protruding bracts. They are ecologically significant, forming extensive forests and providing habitat for diverse wildlife. Commercially, they are highly valued for their strong, durable timber, widely used in construction and woodworking. Their rapid growth and adaptability to different environmental conditions have made them an important species for reforestation and forestry practices.

Anatomy
Anatomy

False Hemlocks, commonly known as Douglas firs, are not true hemlocks but share some similarities. These large, towering trees have a straight, thick trunk and a narrow, conical shape, especially when young. Their bark is thick and deeply grooved. The leaves are flat, soft needles, typically arranged in a spiral on the branches. One of their most distinctive features is the cones, which have unique, three-pointed bracts protruding from between the scales.

These trees grow relatively fast and can live for several hundred years. Douglas firs are known for their significant height, reaching towering sizes, making them prominent in forest landscapes. Their seeds, contained in the cones, play a crucial role in forest regeneration. Adapted to a variety of climates, they are important both ecologically and economically for their high-quality timber.

Cultural Impact
Cultural Impact

False Hemlocks, particularly the Douglas fir, have a significant cultural and economic impact. These trees are a major source of timber, vital to the construction and paper industries due to their strength and durability. Ecologically, they play a crucial role in forest ecosystems, providing habitat for wildlife. Culturally, Douglas firs are celebrated for their majestic presence in the landscape, often symbolizing the wilderness of the Pacific Northwest in the United States.

They are also popular as Christmas trees, cherished for their pleasant scent and full, symmetrical shape. In folklore and indigenous cultures, they hold symbolic meanings, often representing resilience and connection to the land. Their impressive size and longevity have made them a symbol of the natural beauty and richness of forested regions, featuring in various forms of literature, art, and storytelling.

Common Questions
Common Questions
What types of construction materials is Douglas Fir used for

Douglas Fir is often used for framing in residential and commercial buildings, as well as in the construction of bridges, poles, and beams. The wood is also used for siding, roofing, and flooring, and can be finished in a variety of ways to suit different design aesthetics. In addition to its use in traditional wood construction, Douglas fir is also used in the production of engineered wood products, such as laminated veneer lumber and oriented strand board, which are used for structural and non-structural applications.

What is the lifespan of a Douglass Fir tree?

The lifespan of a Douglas fir tree (Pseudotsuga menziesii) can vary depending on a number of factors, including the tree's genetics, environmental conditions, and the presence of diseases or pests. In general, Douglas fir trees can live for several hundred years, with some individuals living for over 1000 years. However, the average lifespan for a Douglas fir tree is typically between 400 and 800 years.

How strong is Douglas Fir?

Douglas fir (Pseudotsuga menziesii) is rated as being comparable to or slightly stronger than other common construction lumber species such as southern yellow pine and spruce-pine-fir. In terms of its mechanical properties, Douglas fir has a high bending strength and stiffness, as well as a good resistance to shock loads. It also has a good weight-to-strength ratio, making it an efficient choice for use in structural applications.

Plants

* Under Development *

49’-82’ | 15-25 m
20’-39’ | 6-12 m (Spread)
20”-59” | .5-1.5 m (Trunk)
.5”-1.25” | 13-32 mm (Needle)
Bigcone Douglas Fir
2500.000
1200.000
150.000
3.200
30
GUIDE
3D
Bigcone Douglas Fir
98’-131’ | 30-40 m
26’-36’ | 8-11 m (Spread)
31”-39” | .8-1 m (Trunk)
.75”-1” | 19-25 mm (Needle)
Chinese Douglas Fir
4000.000
1100.000
100.000
2.500
100
GUIDE
3D
Chinese Douglas Fir
70’-200’ | 21.3-61 m (Typical)
15’-35’ | 4.6-10.7 m (Spread)
47”-79” | 1.2-2 m (Trunk)
.75”-1.5” | 19-38 mm (Needle)
Douglas Fir
6100.000
1070.000
200.000
3.800
52100
GUIDE
3D
Douglas Fir
65’-82’ | 20-25 m
26’-33’ | 8-10 m (Spread)
16”-28” | .4-.7 m (Trunk)
.5”-1” | 15-25 mm (Needle)
Japanese Douglas Fir
2500.000
1000.000
70.000
2.500
40
GUIDE
3D
Japanese Douglas Fir
Bigcone Douglas Fir (Pseudotsuga macrocarpa)
Size comparison drawing of the Bigcone Douglas Fir compared to a person and other False Hemlock species

The name Bigcone Douglas-fir (Pseudotsuga macrocarpa) comes from the large cones it produces. These cones are the largest among trees in this genus. It is also called the bigcone spruce and is found in mountainous areas in southern California. This evergreen conifer has a straight growth form with a conical crown. The roots are strong and spreading while the bark is thin and deeply ridged. The needle-like leaves are shed at five years. The long and spreading main branches have pendulous side shoots, as the seeds are large and heavy. It is mostly planted for habitable restoration as it is resistant to fires, insects, drought, and decay.

Bigcone Douglas Firs have a typical overall height between 49’-82’ (15-25 m) and spread diameter of 20’-39’ (6-12 m). Exceptional mature Bigcone Douglas Fir trees may grow to heights of 100’ (30 m) in the wild. The trunk of the Bigcone Douglas Fir has a diameter of 20”-59” (.5-1.5 m) with needle-like leaf lengths between .5”-1.25” (13-32 mm).

Set of scaled dimensioned drawings of the Bigcone Douglas Fir viewed from the front and top
The name Bigcone Douglas-fir (Pseudotsuga macrocarpa) comes from the large cones it produces. These cones are the largest among trees in this genus. It is also called the bigcone spruce and is found in mountainous areas in southern California. This evergreen conifer has a straight growth form.

Bigcone Douglas Firs have a typical overall height between 49’-82’ (15-25 m) and spread diameter of 20’-39’ (6-12 m). Exceptional mature Bigcone Douglas Fir trees may grow to heights of 100’ (30 m) in the wild. The trunk of the Bigcone Douglas Fir has a diameter of 20”-59” (.5-1.5 m) with needle-like leaf lengths between .5”-1.25” (13-32 mm).

Set of scaled dimensioned drawings of the Bigcone Douglas Fir viewed from the front and top
Bigcone Douglas Fir (Pseudotsuga macrocarpa)
Height:
49’-82’ | 15-25 m
Width:
20’-39’ | 6-12 m (Spread)
Length:
.5”-1.25” | 13-32 mm (Needle)
Depth:
20”-59” | .5-1.5 m (Trunk)
Height (Exceptional)
100’ | 30 m (Max)
Weight:
Area:
Scientific Name
Pseudotsuga macrocarpa

Drawings include:

Bigcone Douglas Fir front elevation, plan view

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Douglas Fir (Pseudotsuga menziesii)
Comparison drawing of the Douglas Fir compared to similar False Hemlock species and a person

You may call it the Douglas spruce, Colombian pine, Oregon pine, or Douglas Fir (Pseudotsuga menziesii). The evergreen conifer tree is native to western North America. There are three varieties. But, unfortunately, it is not a true pine. It can be found in different climatic zones, including mild, wet winters or cool, dry summers. It may be medium or extremely large, with flat, soft green needles having a single fascicle. Young trees have smooth gray barks, while mature trees have dark brown barks. The Douglas Fir favors acidic or neutral soils and self prunes the lower branches when planted on dense forest. The tree is used in forestry management or as a Christmas tree.

Douglas Firs have a typical overall height between 70’-200’ (21.3-61 m) and spread diameter of 15’-35’ (4.6-10.7 m). Exceptional mature Douglas Fir trees may grow to heights of 330’ (100 m) in the wild. The trunk of the Douglas Fir has a diameter of 47”-79” (1.2-2 m) with needle-like leaf lengths between .75”-1.5” (19-38 mm).

Scaled set of drawings of the Douglas Fir in front and top views with dimensions
You may call it the Douglas spruce, Colombian pine, Oregon pine, or Douglas Fir (Pseudotsuga menziesii). The evergreen conifer tree is native to western North America. There are three varieties. But, unfortunately, it is not a true pine. It may be medium or extremely large, with flat green needles.

Douglas Firs have a typical overall height between 70’-200’ (21.3-61 m) and spread diameter of 15’-35’ (4.6-10.7 m). Exceptional mature Douglas Fir trees may grow to heights of 330’ (100 m) in the wild. The trunk of the Douglas Fir has a diameter of 47”-79” (1.2-2 m) with needle-like leaf lengths between .75”-1.5” (19-38 mm).

Scaled set of drawings of the Douglas Fir in front and top views with dimensions
Douglas Fir (Pseudotsuga menziesii)
Height:
70’-200’ | 21.3-61 m (Typical)
Width:
15’-35’ | 4.6-10.7 m (Spread)
Length:
.75”-1.5” | 19-38 mm (Needle)
Depth:
47”-79” | 1.2-2 m (Trunk)
Height (Exceptional)
330’ | 100 m (Max)
Weight:
Area:
Scientific Name
Pseudotsuga menziesii

Drawings include:

Douglas Fir front elevation, plan view

Downloads

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3D Downloads

Japanese Douglas Fir (Pseudotsuga japonica)
Size comparison drawing of the Japanese Douglas Fir compared to a person and other False Hemlock species

The Japanese Douglas-fir (Pseudotsuga japonica) is a rare slow-growing tree also known as ‘Togasawara in Japan, which is its native homeland. It grows in sheltered valleys and steep ravines with temperate forests on silicate volcanic substrates. It is also planted in parks and gardens as an ornamental tree. This monoecious evergreen conifer tree has a longitudinally fissured, dark brown bark turning gray as the tree matures. The shoots are pale yellowish brown while the spirally arranged needles can be linear, straight, or slightly curved. It has the smallest seed cones. Wood from this tree is used in construction and also in making furniture.

Japanese Douglas Firs have a typical overall height between 65’-82’ (20-25 m) and spread diameter of 26’-33’ (8-10 m). Exceptional mature Japanese Douglas Fir trees may grow to heights of 100’ (30 m) in the wild. The trunk of the Japanese Douglas Fir has a diameter of 16”-28” (.4-.7 m) with needle-like leaf lengths between .5”-1” (15-25 mm).

Set of scaled dimensioned drawings of the Japanese Douglas Fir viewed from the front and top
The Japanese Douglas-fir (Pseudotsuga japonica) is a rare slow-growing tree also known as ‘Togasawara in Japan, which is its native homeland. It grows in sheltered valleys and steep ravines with temperate forests on silicate volcanic substrates. It is also ornamentally planted in parks and gardens.

Japanese Douglas Firs have a typical overall height between 65’-82’ (20-25 m) and spread diameter of 26’-33’ (8-10 m). Exceptional mature Japanese Douglas Fir trees may grow to heights of 100’ (30 m) in the wild. The trunk of the Japanese Douglas Fir has a diameter of 16”-28” (.4-.7 m) with needle-like leaf lengths between .5”-1” (15-25 mm).

Set of scaled dimensioned drawings of the Japanese Douglas Fir viewed from the front and top
Japanese Douglas Fir (Pseudotsuga japonica)
Height:
65’-82’ | 20-25 m
Width:
26’-33’ | 8-10 m (Spread)
Length:
.5”-1” | 15-25 mm (Needle)
Depth:
16”-28” | .4-.7 m (Trunk)
Height (Exceptional)
100’ | 30 m (Max)
Weight:
Area:
Scientific Name
Pseudotsuga japonica

Drawings include:

Japanese Douglas Fir front elevation, plan view

Downloads

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3D Downloads

Chinese Douglas Fir (Pseudotsuga sinensis)
Scale illustration of an average Chinese Douglas Fir compared to other species of False Hemlocks and a human

The Chinese Douglas-fir (Pseudotsuga sinensis) is found in China, Taiwan, and some parts of Vietnam. This is in low to medium elevations with moist temperate or warm temperate conditions. This conifer tree produces wood ideal for construction, building, and making furniture. It is an evergreen tree having a gray or dark gray bark that is thickly scaly and corky and branchlets that are pale yellow or yellowish gray. The crown is broad, domed, or flat-topped. The dark green leaves are straight apex obtuse. Female trees produce cones that are pendulous, ovoid, or oblong and purplish, while male strobili are yellowish. The seeds are light-brown and cuneate ovoid.

Chinese Douglas Firs have a typical overall height between 98’-131’ (30-40 m) and spread diameter of 26’-36’ (8-11 m). Exceptional mature Chinese Douglas Fir trees may grow to heights of 164’ (50 m) in the wild. The trunk of the Chinese Douglas Fir has a diameter of 31”-39” (.8-1 m) with needle-like leaf lengths between .75”-1” (19-25 mm).

Pair of dimensioned illustrations of the Chinese Douglas Fir seen from the top and elevation views
The Chinese Douglas-fir (Pseudotsuga sinensis) is found in China, Taiwan, and some parts of Vietnam. This is in low to medium elevations with moist temperate or warm temperate conditions. This conifer tree produces wood ideal for construction, building, and making furniture.

Chinese Douglas Firs have a typical overall height between 98’-131’ (30-40 m) and spread diameter of 26’-36’ (8-11 m). Exceptional mature Chinese Douglas Fir trees may grow to heights of 164’ (50 m) in the wild. The trunk of the Chinese Douglas Fir has a diameter of 31”-39” (.8-1 m) with needle-like leaf lengths between .75”-1” (19-25 mm).

Pair of dimensioned illustrations of the Chinese Douglas Fir seen from the top and elevation views
Chinese Douglas Fir (Pseudotsuga sinensis)
Height:
98’-131’ | 30-40 m
Width:
26’-36’ | 8-11 m (Spread)
Length:
.75”-1” | 19-25 mm (Needle)
Depth:
31”-39” | .8-1 m (Trunk)
Height (Exceptional)
164’ | 50 m (Max)
Weight:
Area:
Scientific Name
Pseudotsuga sinensis

Drawings include:

Chinese Douglas Fir front elevation, plan view

Downloads

2D Downloads

3D Downloads