Firs (Abies) belong to a genus of 48 to 56 species of evergreen trees. They are classified under the family Pinaceae. They are mostly found in Central and North America, Asia, Europe, and North Africa. Many other coniferous trees are called firs such as Douglas fir (Pseudotsuga), joint fir (Ephedra), and the hemlock fir (hemlock), but these are not true firs. Many types of firs are used as a source of timber and many are cultivated as ornamentals such as Christmas trees.
Table of Contents
- Distinguishing Features of Fir
- Basis of Identification of Fir Species
- Characteristics of Firs
- Types of Fir Wood
- 1. Balsam Fir (Abies balsamea)
- 2. Fraser Fir (Abies fraseri)
- 3. Grand Fir (Abies grandis)
- 4. Himalayan Fir (Abies pindrow)
- 5. Korean Fir (Abies koreana)
- 6. Noble Fir (Abies procera)
- 7. Nordmann Fir (Abies nordmanniana)
- 8. Red Fir (Abies magnifica)
- 9. Silver Fir (Abies Alba)
- 10. Spanish Fir (Abies pinsapo)
- 11. Subalpine Fir (Abies lasiocarpa)
- 12. White Fir (Abies concolor)
Distinguishing Features of Fir
They are distinguished from other trees in the pine family by their characteristic leaves. Their leaves are needle-like and are attached singly to its branches that resemble a suction pump. The cones of firs stand upright like candles which disintegrate as they mature. They are softer than that if coniferous trees. The needles of firs detach from their branches cleanly without leaving behind a peg. The needles are not formed as clusters or into fascicles.
Basis of Identification of Fir Species
Different species of firs are identified on the basis of the arrangement and size of the leaves, the shape and size of the cones, and the type of bract scales (short and hidden inside a cone or long and exserted).
Characteristics of Firs
As mentioned earlier, fir leaves are the characteristic feature of fir trees that distinguishes them from the rest of the trees. Fir leaves are flattened significantly, so much that sometimes, fir leaves may seem to be pressed.
Leaves have two white-colored lines on the bottom. These lines are formed by the stomatal bands that are covered by wax. The upper surface of the leaves is green and shiny without any stomata in most types of firs. However, in a few species, some stomata may be present on the tips that are quite visible as white spots. In some types of firs, the leaves are dull-green, gray-green, silvery or bluish-gray in color, with a coating of wax with varying numbers of stomatal bands which are not always continuous.
The tips of fir leaves are usually notched but they may be rounded or dull sometimes. They can also be prickly and sharp. The leaves of young fir plants are usually sharper.
Leaves spread from the shoot diversely. They are comb-shaped in some species, having flat leaves arranged on two sides.
Firs have erect and cylindrical cones that are about 2 to 10 inches long. They disintegrate upon maturity and release winged seeds. Even in larger trees, the cones do not hang but stay erect like candles. The color of young cones is usually green in summers that turn into brown as they mature. Cones can be a dark purple or blue too, as in Abies fraseri.
Types of Fir Wood
Most species of Fir trees in America are found in the northern region. They are found in the area from the Rocky Mountains towards the west and attain full development in Cascade and Sierra Nevada ranges. The most commonly found types of firs are listed down below:
This North American fir is native to eastern and central Canada and the northeastern United States. It is popular for its rich green colored needles, natural conical shape and the retention of needles after being cut. It is one of the most fragrant varieties for Christmas trees.
Balsam fir an evergreen tree that is small to medium in size. It is typically 14 to 200 meters tall. They can reach a height of 27 meters occasionally. Balsam fir trees have a narrow cone-shaped crown that has densely arranged dark-green colored leaves.
Young trees have a smooth, grey colored bark with resin blisters. It becomes fissured and rough or scaly as the tree grows old. The leaves are needle-like and flat. They are dark green on the surface and have a small stomatal patch near the tip. Two white colored stomatal bands are found below the leaves. The tip is slightly notched. Leaves are arranged in a spiral fashion on the shoot but twisted at the base. Seed cones are erect and dark purple that turn brown when ripe. They disintegrate in September to release winged seeds.
This type of fir is native to the Appalachian Mountains in the southeastern United States. Fraser fir is related closely to balsam fir. It is an evergreen tree that is usually 10 to 15 meters tall. It rarely grows to a height of 25 meters. It has a conical crown. The branches are straight which can be horizontal or angled upwards at an angle of 40o from the trunk. The young tree is dense. It opens as the tree matures.
The bark of Fraser fir is smooth and thin with many resinous blisters. The bark becomes scaly as the tree matures. The leaves of Fraser fir are needle-shaped and arranged spirally. They are twisted at the base. They are flat, broad, and flexible. They are rounded or notched slightly at the tips. They are dark green on the surface with small white colored stomatal patches near the apices. On the underside, they have two white colored stomatal bands.
Seed cones are erect and dark purple that turns pale brown on maturity.
Grand fir is native to Northern California and Pacific Northwest of North America. It is a large, evergreen tree that is usually 40 to 70 meters tall. They can sometimes grow to be as tall as 100 meters.
The bark is smooth. It is grayish-brown in color with resinous blisters and white spots. The bark becomes scaly as the tree become old. The leaves of Grand fir are flat and needle-like. They are shiny, dark green on the upper surface with two green-white stomatal bands on the underside. The leaves are notched slightly at the tip. The leaves are arranged spirally. Each leaf is twisted at the base, thus they make two or more flat rows on each side of the shoot so that the leaves are coplanar. The lined up leaves in a flat plane help distinguishing this type of fir.
The cones are broad and scaly. The scale bracts of Grand fir are short and hidden inside a closed cone. The cones disintegrate to release winged seeds.
These types of fir are native to western Himalaya, from northeast Afghanistan to northern Pakistan and India. It is a large, evergreen tree, usually 40 to 60 meters tall. It has a conical crown.
The shoots of Himalayan fir are smooth and grayish-pink to brown in color. The leaves are needle-shaped. They are shiny and dark green on the upper side with two white colored stomatal bands on their underside. Their arrangement on shoots is spiral. They are twisted at the base.
The cones are broad and cylindrical. Young cones are dark purple in color. They disintegrate to release seeds after they are mature.
Korean fir is native to South Korea. It is an evergreen tree that grows to about 10 to 18 meters tall.
The bark is smooth and dark brown in color. It contains resinous blisters. The leaves are flat and needle-like. They are glossy and dark green on the upper side while on the underside, two board, white-colored stomatal bands are present. The leaves are notched slightly at the tip. The leaves are arranged spirally. The leaves are twisted at the base. The young shoots are green-grey in color but as they mature, they become pinkish-grey.
The cones are broad. Before maturity, they are purple-blue in color. Cones have long scale bracts. Cones disintegrate to release winged seeds.
Noble fir is a western North American tree that is native to the Cascade Range and the Coast Range mountains. They are large, evergreen trees that grow up to 70 meters tall. They have a narrow cone-shaped crown.
The young bark is smooth and gray in color. It has a resinous blisters. The bark becomes rough and brown in color as the tree matures. The leaves of Noble fir are needle-like. The green on the upper surface with strong stomatal bands on the underside. The leaves are arranged spirally and like leaves of all other types of fir, they are twisted at the base.
The cones of these firs are erect with purple scales. The scale bracts are long and exserted. The cones disintegrate and release winged seeds.
Nordmann fir trees are found on the mountains east and south of the Black Sea in Turkey, the Russian Caucasus, and Georgia. They are evergreen and large trees that can grow to be as tall as 55 to 61 meters.
The leaves of this species are flat and needle-like. They are glossy and dark green on the surface and have two bluish-white bands of stomata on their underside. The tip of leave sis blunt. They are slightly notched at the tip.
The cones of Nordmann fir are broad and scaly. The scales are exserted and have two winged seeds which are released when the cone disintegrates. The lifespan of this fir is longer than other firs.
Red fir is native to mountains of California and southwest Oregon. They are evergreen trees that are fairly large, growing to heights of 40 to 60 meters. They rarely grow to up to 77 meters. They have a narrow conic crown.
The bark of young red firs is smooth and gray in color. It has blisters on it. The bark turns rough, fissured, and orange-red when the tree grows old. The leaves are needle-shaped. The upper surface of leaves is green while on the underside, the leaves have stomatal bands that are quite prominent. The leaves are arranged in a spiral fashion, slightly up-curved above the shoot.
The cones of Red fir are erect. They are yellow-green in colors that become brown when ripe. They disintegrate to release winged seeds.
Silver fir is native to Southern and central Europe. They are large trees with a height of about 55 meters. They have a pyramidal crown that becomes flat as the tree ages.
The bark of Silver fir is smooth and gray in color with scales and resinous blisters on it. Leaves are needle-like with a twisted base and a notched apex. The upper surface, like other species, is glossy and dark green while the lower surface of the leaves white stomatal bands.
The cones are cylindrical and blue, violet or red in color. Young cones are green but they turn brown when they are mature. Winged seeds are released when mature cones disintegrate.
This species of fir is native to Northern Morocco and Southern Spain. Spanish fir is an evergreen tree that grows to about 20 to 30 meters tall. They have a cone-shaped crown that becomes irregularly shaped like the tree ages.
The leaves of Spanish fir are arranged all around the shoot, radially. They are dull blue-green in color with broad, white colored bands of stomata on both sides of the leaf.
The bark is smooth when young but it becomes rough and fissured with age. The cones are cylinder shaped. Young cones are greenish-pink in color but they turn purple before maturity. The cones are smooth with short bract scales that are not exserted. They disintegrate to release winged seeds.
Subalpine fir is native to Western North America. It is of medium size, growing up to 20 meters in height, sometimes up to 50 meters tall. They have a narrow crown that is cone shaped.
The young bark is gray in color and smooth with resinous blisters. It becomes rough and fissured as the tree ages. The leaves of this fir tree are needle-like and flat. They are dull green on the upper surface with a broad stomatal stripe and two bluish-white stomatal bands on the underside. Leaves are arranged in a spiral manner, with twisted base.
The cones of subalpine fir are erect with blackish-purple color. They ripen to become brown. They release winged seeds upon maturation.
Native to western North America, White fir is an evergreen tree that can grow to a height of 75 meters.
The leaves of White fir are flat and needle-like. They are a shade of dull blue-green on the upper surface with two dull blue-white colored stomatal bands on the lower surface. Leaves are arranged spirally and are slightly notched at tips. Each leaf is twisted at the base.
The cones are green colored that becomes purple when ripe. Cones are broad and scaly. Scale bracts are short and hidden inside the cone. Cones din integrate at maturity to release winged seeds.
Different types of firs have different leaf arrangement, unique stomatal bands, and distinctive cone colors that help in their identification. Firs are the most popular trees that are used as Christmas trees.