DEFINITION OF CONIFER - CONIFEROUS FOREST



Conifer is any one of a large group of trees or shrubs that bears its seeds in cones. Most conifers have tall, straight trunks and narrow branches and grow in cold or cool climates. Common conifers include cedars, cypresses, firs, hemlocks, junipers, larches, pines, redwoods, sequoias, and yews. The cycad plant also bears cones, but it is not considered to be a conifer.

Conifers are one of the oldest groups of woody plants. Conifer fossils have been found in rocks that are about 300 million years old. Conifers include the largest, tallest, and oldest living things. The largest giant sequoia is about 275 feet (83.8 meters) high, and the base of its trunk has a circumference of 103 feet (31.4 meters). Redwoods, the tallest living trees, may tower more than 360 feet (110 meters) high. Some bristlecone pines are more than 4,600 years old.

Conifers form about 30 per cent of the world's forests. In North America, most of the wood used in houses and other buildings comes from conifers, especially Douglas-fir and loblolly pine. Conifers also provide much wood pulp for making paper and cardboard. In addition, millions of conifers are used every year as Christmas trees.

In southern Canada the Taiga mingles with the temperate deciduous forest in some places. In northern Canada, the Taiga gradually tapers off, and the Arctic Tundra begins. The Siberian Taiga in Russia and Asia often has taller trees.

The main feature of the northern temperate zone of Asia is the presence and great importance of conifer species. Their distribution is generally restricted to the temperate zone, while summer-green broadleaved species are dominant over the whole territory. Because of high fire sensitivity, the nemoral conifers can easily disappear from the communities leaving a great question for researchers; whether the pure broadleaved forests in densely populated and severely deforested regions were originally summer-green broadleaved or whether they used to be mixed with conifers before human influence. Conifer forests in those regions occur in very small areas, as a rule – not comparable in size with the areas of broadleaved forests.
On the other hand, many conifer species are adapted to extreme edaphic conditions within the temperate zone, such as water deficit, wind exposure, nutritionally poor soils, slope processes and others.

Coniferous Forest 


The Coniferous forest, located along the northern California coast, contains the largest life-form on Earth! The giant Sequoia trees are also the longest-lived life form on Earth. Some of these trees are 3,000 years old and counting!. Some coniferous trees depend on fire as a catalyst for seed-release. The Lodgepole Pine tree is an example of this kind of tree. The seeds develop in the pinecones, but unlike other conifers whose pinecones ripen and open to release the seeds, the Lodgepole's cones never ripen. The heat from naturally occurring fires force the Lodgepole Pine tree's serotinous cones to burst open, thus releasing the tree's seeds.

Temperature

-40°C to 20°C, average summer temperature is 10°C

Precipitation

300 to 900 millimeters of rain per year

Vegetation

Coniferous-evergreen trees (trees that produce cones and needles; some needles remain on the trees all year long)

Location

Canada, Europe, Asia, and the United States

Other

Coniferous forest regions have cold, long, snowy winters, and warm, humid summers; well-defined seasons, at least four to six frost-free months

 

Most conifers are evergreen and have small, needlelike leaves. Other conifers, including redcedars and cypresses, have tiny, scalelike leaves that cling to the stem. These trees are also evergreen. Larches and baldcypresses are conifers but they lose their leaves every year.

Conifer cones range from less than 1/2 inch (1.3 centimeters) long to more than 2 feet (61 centimeters) long. Conifers have two types of cones--male and female. In most conifers, both types grow on the same plant. The soft male cones produce and release pollen, then shrivel and die. The female cones are larger and become woody with age. Each of their scales has two structures called ovules, which contain eggs (female reproductive cells). Wind carries pollen from the male cones to the female cones, where the pollen fertilizes the egg. The ovules then develop into seeds. After the seeds become fully formed, they fall from the cones.

A few conifers have unusual, fleshy cones. Juniper seed cones resemble blueberries. Yew seed cones look like red berries with a single, large seed.
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