Pine Tree
Pine (tree) is a common name for a medium-size family of trees, mostly evergreen, of widespread distribution in the temperate areas of the northern hemisphere, and for its representative genus. The family, which contains about 210 species placed in 10 genera, has enormous economic importance as a source of timber and pulpwood, among other products. Members of the family characteristically have helically arranged, needlelike leaves. In several genera—for example, pine, cedar, and larch—the leaves are borne in clusters that are actually short branches, or spurs, on which the leaves are arranged in tight helices.
Pines are divided into two groups, based on the scale leaves and other characteristics. The soft pines have leaves in bundles of five, and the scale leaves fall away from mature leaf bundles. Their wood is soft and has a coarse grain. Well-known soft pines are the eastern white pine, of northeastern North America; piñon pine, of the Southwest, the seeds of which are edible; bristlecone pine, the Rocky Mountain species; and the Great Basin bristlecone, which can live more than 5000 years and is the oldest known living thing on the planet. Through analysis of bristlecone rings, scientists can tell what the climate was more than 10,000 years ago. The hard pines have leaves in clusters of two or three, and the scale leaves persist in mature clusters. The wood is usually hard, with a close grain. Well-known species include lodgepole pine, extending from Alaska to Baja California; longleaf pine, of the southeastern coastal plain; and ponderosa pine, of the American West. Both pine groups are economically important for their timber, pulp, tar, and turpentine and for their use as ornamentals. Members of a pine family thought to be extinct for 50 million years were discovered in a rain forest near Sydney, Australia, in 1994. Other members of the pine family include Douglas fir, hemlock, and spruce.
Scientific classification: Pines make up the family Pinaceae. Its representative genus is Pinus. Cedars are classified in the genus Cedrus, the larches in the genus Larix, firs in the genus Abies. The genus confined to South China and Southeast Asia is Keteleeria. The golden larch is classified in the genus Pseudolarix. The eastern white pine is classified as Pinus Strobus, the piñon pine as Pinus edulis, and the bristlecone pine as Pinus aristata. The Great Basin bristlecone is classified as Pinus longaeva, the lodgepole pine as Pinus contorta latifolia, the longleaf pine as Pinus palustris, and the ponderosa pine as Pinus ponderosa. The newly discovered Australian conifers belong to Auracariaceae, a family of primitive trees.
Pines are divided into two groups, based on the scale leaves and other characteristics. The soft pines have leaves in bundles of five, and the scale leaves fall away from mature leaf bundles. Their wood is soft and has a coarse grain. Well-known soft pines are the eastern white pine, of northeastern North America; piñon pine, of the Southwest, the seeds of which are edible; bristlecone pine, the Rocky Mountain species; and the Great Basin bristlecone, which can live more than 5000 years and is the oldest known living thing on the planet. Through analysis of bristlecone rings, scientists can tell what the climate was more than 10,000 years ago. The hard pines have leaves in clusters of two or three, and the scale leaves persist in mature clusters. The wood is usually hard, with a close grain. Well-known species include lodgepole pine, extending from Alaska to Baja California; longleaf pine, of the southeastern coastal plain; and ponderosa pine, of the American West. Both pine groups are economically important for their timber, pulp, tar, and turpentine and for their use as ornamentals. Members of a pine family thought to be extinct for 50 million years were discovered in a rain forest near Sydney, Australia, in 1994. Other members of the pine family include Douglas fir, hemlock, and spruce.
Scientific classification: Pines make up the family Pinaceae. Its representative genus is Pinus. Cedars are classified in the genus Cedrus, the larches in the genus Larix, firs in the genus Abies. The genus confined to South China and Southeast Asia is Keteleeria. The golden larch is classified in the genus Pseudolarix. The eastern white pine is classified as Pinus Strobus, the piñon pine as Pinus edulis, and the bristlecone pine as Pinus aristata. The Great Basin bristlecone is classified as Pinus longaeva, the lodgepole pine as Pinus contorta latifolia, the longleaf pine as Pinus palustris, and the ponderosa pine as Pinus ponderosa. The newly discovered Australian conifers belong to Auracariaceae, a family of primitive trees.
Comments