Needleleaf forest is composed largely of straight trunked, conical tress with relatively short branches, and small, narrow, needlelike leaves. These tress are conifers. Where evergreen, the needleleaf forest provides continues and deep shade to the ground so that lower layers of vegetation are sparse or absent except for a thick carpet of mosses in many places. Species are few and large tracts of forest consist almost entirely of but one or two species.
Reference to the world vegetation map will show that needleleaf forest is predominantly in two great continental belts, one in North America and one in Eurasia, which span the landmasses from west to east in latitudes 45° to 75°. The needleleaf forest of North America, Europe and western Siberia is composed of evergreen conifers, such as spruce (Picea), fir (Abies) and pine (Pinus), whereas that of north-central and eastern Siberia is dominantly of larch (Larix) which sheds its needles in winter and comprises a deciduous forest. Associated with the needleleaf tress is mountain ash. Aspen and balsam poplar (Populus), willow, and brich tend to take over rapidly in areas of needleleaf forest, which have been burned over, or can be found bordering streams and in open places.
Needleleaf evergreen forest extends into lower latitudes wherever mountain range and high plateaus exist. Thus in western North America this formation class extends southward into the United States on the Cascade, Sierra Nevada, and Rocky Mountain ranges and over parts of the higher plateaus of the southwestern states. In Europe, needleleaf evergreen forests flourish on all of the higher mountain ranges, and well into Scandinavia.
The needleleaf evergreen forests of British Columbia and California are of particular interest. Here, under a regime of heavy orographic precipitation and prevailing high humidities, are perhaps the densest of all coniferous forests, with the world's largest trees. Forests of coastal redwood, big tree and Douglas' fir are particularly remarkable. Individuals of redwood and big tree attain heights of over 325 ft (100 m) and girths of over 65 ft (20 m).
As much of the area of needleleaf evergreen forest in North America and Europe was subjected to glaciation in the Wisconsin stage of the Pleistocene epoch, there abound lakes and poorly drained depressions.
Podzolization, the pedogenic regime of the needleleaf forest, is a direct result of a climate regime of continentality with a strong polar influence.
"The world is a book, and those who do not travel read only a page", St. Augustine said. Here at www.travel-university.org we believe that every page must be read and explored. Travel is an avenue of learning that no text or classroom can teach. The world is a living classroom and you the student. We invite you to the www.travel-university.org library where you can read general interest and detail oriented articles.
