Firs (Abies) are a genus of 48–56 species of evergreen coniferous trees in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range. Firs are most closely related to the genus Cedrus (cedar). Douglas firs are not true firs, being of the genus Pseudotsuga.
The genus name is derived from the Latin "to rise" as a reference to their height. The common English name originates with the Old Norse, fyri, or the Old Danish, fyr.
They are large trees, reaching heights of 10–80 m (33–262 ft) tall with trunk diameters of 0.5–4 m (1 ft 8 in–13 ft 1 in) when mature. Firs can be distinguished from other members of the pine family by the way in which their needle-like leaves are attached singly to the branches with a base resembling a suction cup, and by their cones, which, like those of true cedars (Cedrus), stand upright on the branches like candles and disintegrate at maturity.
Identification of the different species is based on the size and arrangement of the leaves, the size and shape of the cones, and whether the bract scales of the cones are long and exserted, or short and hidden
inside the cone.
The total area of fir forests is about 18 million hectares. Firs are common in temperate (taiga and subtaiga (coniferous-deciduous), as well as in mountainous and foothill, in some cases even in flat areas (at some elevations, in particular, in Normandy) outside the taiga and subtaiga zones, far to the south of them, for example, white fir in Western and Central Europe), subtropical and tropical regions of the Northern hemisphere, including Mexico, Guatemala, Honduras and El Salvador. In the north, they go beyond the Arctic Circle (Siberian fir in the lower reaches of the Yenisei is the only polar location of the range of the genus Abies, the northernmost tip of which is located, according to earlier data, in the area of 67 ° s. w., according to later data — at 69 ° s. w.), and in the south they spread below 14 ° s. w. (Guatemalan fir). Depending on the geographical and climatic features of the habitats, they grow almost from sea level (temperate latitudes, for example, balsamic fir) to 3500-4000 m above sea level, and sometimes slightly higher (subtropics and tropics, for example, wonderful fir and Guatemalan fir). The most species-rich areas are the Pacific coast of Asia and North America. There are 7 known species on the territory of the Russian Federation: Siberian (Abies sibirica), Caucasian, or Nordman fir (Abies nordmanniana), Sakhalin (Abies sachalinensis), Mayra fir (Abies mayriana), kidney-leafed (Abies nephrolepis), whole-leaved (Abies holophylla), graceful (Abies gracilis). Unlike larch and spruce trees that are undemanding to heat, firs are heat-loving trees, and most of their species tend in their natural distribution to the mid-latitude and southern regions of the Northern Hemisphere with a mild climate. Very many species are characterized by low frost resistance, and others are almost completely frost-resistant, such as, for example, Guatemalan fir and sacred fir. Frost-resistant are mainly firs, common in the taiga zone of the Northern hemisphere, but they are also significantly inferior in frost resistance to larches and firs of the North, which are widespread in more severe areas not only of the taiga, but also of the forest tundra. In addition, fir trees are demanding on soil fertility and the humidity regime of habitats. Exceptionally shade-tolerant at all ages and often very shade-loving at a young age.
Meaning and application
The wood is white, without a core, with a yellowish tinge, without resin passages, light in dry form, has low strength and low elasticity, is easily pricked and processed. It is used in construction (it has the lowest coefficient of thermal conductivity among other breeds - 0.037 W / (m * K) - this is 4½ times lower than that of oak, 2½ times lower than that of cedar and pine, and is equivalent to expanded polystyrene and glass wool - this explains that fir was used for the construction of their log cabins by chilig and yaylyg indigenous Siberian peoples), pulp and paper industry, carpentry and furniture production. Firewood and charcoal are of poor quality.
Fir balsam is obtained from the bark, essential fir oil is obtained from the needles. Seeds contain up to 30% of fatty oils suitable for the production of lacquers. The swellings on the bark (nodules) contain oleoresin, called fir, or Canadian balsam, from which turpentine, rosin, medicines, varnishes and glue are obtained, used in the optical industry for gluing lenses (it has the same angle of refraction of rays with glasses and does not distort images) and in the preparation of micropreparations.
Used in landscaping. Due to its sensitivity to atmospheric pollution, fir is unsuitable for breeding near factories and factories, along highways, etc. Fir forests have climate-regulating, water-regulating, water protection and soil protection significance. In Siberia, they are rich hunting grounds.