|Abies - firs|
|Korean Fir (Abies koreana) cone and foliage|
Firs (Abies) are about 45-55 species of evergreen trees in the family Pinaceae. Fir trees can reach heights of 10–80 m tall and trunk diameters of 0.5–4 m when mature. The difference between firs and other members of the pine family is that their needle-like leaves are attached to the twig by a base that resembles a small suction cup, and by erect, cylindrical female cones 5–25 cm long that release the winged seeds. The male cones are normally much smaller and spread through the tree so that the wind can help pollinate the female cones.
Like all members of the pine family, these trees have a sticky sap called resin.
Fir wood is not suitable for construction because it is not very resistant to insects and decay. It is usually sawn or crushed into fine sheets or pieces and made into plywood or chipboard for indoor or temporary outdoor use. However, fir trees are used widely in gardening. They can be used as shelter trees to protect other plants from wind or grown alone as decorative trees.
Atypical A. alba foliage from Dinaric calcareous fir forests on 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. Other species have the upper surface of leaves dull, gray-green or bluish-gray to silvery (glaucous), coated by wax with variable number of stomatal bands, and not always continuous. An example species with shiny green leaves is A. alba, and an example species with dull waxy leaves is A. concolor.
The tips of leaves are usually more or less notched (as in A. firma), but sometimes rounded or dull (as in A. concolor, A. magnifica) or sharp and prickly (as in A. bracteata, A. cephalonica, A. holophylla). The leaves of young plants are usually sharper.
The way they spread from the shoot is very diverse, only in some species comb-shaped, with the leaves arranged on two sides, flat (A. alba)
Mature cones are usually brown, young in summer can be green, for example:
- A. grandis, A. holophylla, A. nordmanniana
or purple and blue, sometimes very dark:
- A. fraseri, A. homolepis (var. umbellata green), A. koreana ('Flava' green), A. lasiocarpa, A. nephrolepis (f. chlorocarpa green), A. sibirica, A. veitchii (var. olivacea green).
Fir Facts for Kids. Kiddle Encyclopedia.