NOT ONLY CHRISTMAS TREE…
A cone is a characteristic organ discriminating the conifers from other Gymnosperms. These plants do not develop any fruit, and they are dispersed by seeds, hidden between cone scales. Thus, Gymnosperms are separated from other plants bearing flowers and fruits, and called Angiosperms Many species of conifers are trees, some are shrubs. This group comprises approximately 630 species, including such as: cedars, Douglas-firs, cupresses, firs, larches, pines, redwoods, spruces, and yews. Yews, in Latin called Taxus
, do not develop cones, and their seeds covered by a red aril are easily accessible for birds. Conifers form the boreal forests in the northern hemisphere. They are also common in the upper forest zone in mountains, where cool climates dominate. Species of conifers can be quickly determined by shapes of cones, needle-like leaves or patterns of bark sculpture.
In European mountains, spruces, pines, firs and larches are main components of the coniferous forest zone. In North American Rocky Mountains, within the species Pinus longaeva
the oldest trees of the world were found, ca 5000 years old. Also giant cupresses and redwoods decorate American mountains. Many conifers have evergreen leaves, but larches reject soft needles before winter season, they are deciduous.
Conifer wood is composed of tracheids and resin ducts, and shows very distinct annual rings. A ring patern is used for detection of climate changes in the past. Mainly spruces and pines were used by people, less than a century ago, for building houses, bridges, ships and vehicles.At present the coniferous forests are protected to maintain biodiversity of the fragile mountain ecosystems.
In mountains we can admire beautiful specimens of conifers presenting regularly shaped crowns.
It will be continued...
No comments posted yet.