Fir

Firs are evergreen coniferous trees belonging to the genus Abies ('eIbi%iz) in the family Pinaceae. There are approximately 48–56 extant species, found on mountains throughout much of North and Central America, Europe, Asia, and North Africa. The genus is most closely related to Cedrus (cedar). The genus name is derived from the Latin "to rise" in reference to the height of its species. The common English name originates with the Old Norse, fyri, or the Old Danish, fyr. They are large trees, reaching heights of tall with trunk diameters of 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, 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. Abies alba PID1015-3.jpg|''[[Abies alba|A. alba]]'' – the underside of leaves have two whitish strips formed by [[wax]]-covered [[stoma]]tal bands; the bases of the needles are shaped like suction cups. Abgragra-top.jpg|''[[Abies grandis|A. grandis]]'' foliage – upper side of the leaves Abies Orjen foliage.jpg|Atypical ''[[Abies alba|A. alba]]'' foliage from [[Dinaric Alps|Dinaric]] [[calcareous]] fir forests on [[Orjen|Mt. Orjen]] Firs can be distinguished from other members of the pine family by the unique attachment of their needle-like leaves to the twig by a base that resembles a small suction cup. The leaves are significantly flattened, sometimes even looking like they are pressed, as in A. sibirica. The leaves have two whitish lines on the bottom, each of which is formed by wax-covered stomatal bands. In most species, the upper surface of the leaves is uniformly green and shiny, without stomata or with a few on the tip, visible as whitish spots.