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A pine is any conifer tree or shrub in the genus Pinus ( / ˈpaɪnəs /) [1] of the family Pinaceae. Pinus is the sole genus in the subfamily Pinoideae. World Flora Online accepts 187 species names of pines as current, with additional synonyms, making it the largest family among the conifers. [2] .
The meaning of PINE is any of a genus (Pinus of the family Pinaceae, the pine family) of coniferous evergreen trees that have slender elongated needles and include some valuable timber trees and ornamentals. How to use pine in a sentence. Synonym Discussion of Pine.
- Overview
- Major Eurasian pines
pine, (genus Pinus), genus of about 115 species of evergreen conifers of the pine family (Pinaceae), distributed throughout the world but native primarily to northern temperate regions. Pines and other conifers are key members of the taiga (boreal forests), coniferous forests, and mixed forests throughout the world, and many pine species are iconic or characteristic constituents of a number of specific ecosystems, such as the longleaf pine (Pinus palustris) ecosystem of the southern United States. Like all trees, the plants provide habitat and a variety of other ecosystem services, and pine seeds are an important food source for birds, squirrels, and other animals. The chief economic value of pines is in the construction and paper-products industries, but they are also sources of turpentine, rosin, oils, and wood tars. Edible pine seeds, which are sold commercially as pine nuts, pignoli, piñons, or pinyons, are produced by several species. Many pines are cultivated as ornamentals, including black, white, Himalayan, and stone pines, and some are planted in reforestation projects or for windbreaks. Pine-leaf oil, used medicinally, is a distillation product of the leaves; charcoal, lampblack, and fuel gases are distillation by-products.
Pines are softwoods, but commercially they may be designated as soft pines or hard pines. Soft pines, such as white, sugar, and piñon pines, have relatively soft timber, needles in bundles of five (less commonly, one to four), stalked cones with scales lacking prickles, and little resin. Their wood is close-grained, with thin, nearly white sapwood; the sheaths of the leaf clusters are deciduous, and the leaves contain a single fibrovascular bundle. Hard pines, such as Scotch, Corsican, and loblolly pines, have relatively hard timber, needles in bundles of two or three (rarely, five to eight), cone scales with prickles, and large amounts of resin. Their wood is coarse-grained and usually dark-coloured, with pale, often thick sapwood; the sheaths of the leaf clusters are persistent, and the leaves have two fibrovascular bundles.
Young pine trees are usually conical, with whorls of horizontal branches. Older trees may have round, flat, or spreading crowns. Most species have thick rough furrowed bark. Pines have two types of branches, long shoots and short shoots, and three types of leaves, primordial, scale, and adult. Seedling plants bear the lance-shaped spirally arranged primordial leaves. The triangular scale leaves, also lance-shaped, are borne on the long shoots of older trees. Both long and short shoots develop in the axils of the deciduous scale leaves. The needlelike photosynthetic adult leaves, with two or more resin canals, are borne in fascicles (bundles) of two to five (rarely, up to eight or solitary) at the tip of each short shoot; they remain on the tree 2 to 17 years.
Pollen-bearing male cones are covered with many fertile scales, each of which bears two pollen sacs. Ovule-bearing female cones, borne on the same tree, have several spirally arranged bracts (modified leaves), each of which is located below a scale with two ovules (potential seeds). In spring or early summer the pollen sacs release pollen through longitudinal slits; each grain has two air bladders for wind dispersal. The scales on the female cones open to receive the pollen and then close; actual fertilization takes place late the following spring. After fertilization, the woody female cone develops over a two- to three-year period. In some species the cones open at maturity and the seeds are released, while in others the cones remain closed for several years until opened by rotting, by food-seeking animals, or by fire. In some pines the scale bearing the nutlike seed may be expanded to form a wing for airborne dispersal.
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Trees of the World
The Scotch pine (P. sylvestris) of northern Europe, when grown under optimum conditions, attains a height of 20 to 40 metres (70 to 130 feet). It is conical in youth, acquires a mushroom-shaped crown in maturity, and has a straight trunk as much as one metre (about three feet) in diameter, fiery red-brown bark, and gnarled, twisted boughs densely clothed with blue-green foliage at the extremities. Scotch pine occurs in varying abundance from Finland and Sweden to the mountains of Spain and the higher slopes of Mount Etna and, longitudinally, from the shores of the North Sea to Siberia. Abundant in the Scandinavian Peninsula, it is the “fir” (fur, fura) of the old Norsemen and still retains that name in Great Britain, although it is a true pine. Economically, it is valued for timber and also for turpentine and tar.
Closely allied to the Scotch pine is the mugo pine (P. mugo), a recumbent bush or small tree, generally only a metre or two (3 to 6.5 feet) high, which often has long zigzag stems that root occasionally at the kneelike bends where they rest upon the ground. It abounds in the Bavarian and Tirolese Alps.
The Austrian, or black, pine (P. nigra) grows to a height of 30 or even 45 metres (98 to 148 feet), with a straight trunk and branches in regular whorls, forming in a large tree a pyramidal head. It derives its name from the sombre aspect of its dark green, sharp, rigid, rather long leaves. The tree displays a deeply fissured bark and light brown branches. This species, widely cultivated as an ornamental, is native to Europe and western Asia.
The cluster pine, or pinaster (P. pinaster), a vigorous grower in coastal sand, has been cultivated extensively for the purpose of stabilizing sand drifts, especially on the dunes of the Bay of Biscay and the Mediterranean. It grows to a height of 12 to 24 metres (39 to 79 feet), and the deeply furrowed trunk occasionally reaches a diameter of a metre or more at the base. Forests of pinaster, apart from the production of timber, have great economic value as a source of turpentine.
Italian stone pines (or umbrella pines, P. pinea) are native to the Mediterranean region and have naturalized in many places. Their spreading rounded canopies of light green foliage, supported on a tall and often branchless trunk, form a particularly striking feature of the landscape of Italy. The cones have been prized from the days of ancient Rome for their edible seeds (pignoli), which are still used for food.
The Himalayan white pine (or blue pine, P. wallichiana) differs chiefly from the Italian stone pine in its longer cones and drooping glaucous foliage. It grows in parts of India, in Bhutan, and on some of Nepal’s ranges, where it attains large dimensions.
- The Editors of Encyclopaedia Britannica
- Pine Tree Identification. Pine trees can be identified by their needle-like leaves, seed-bearing cones, and reddish-brown or gray bark. Another identifying feature of pine trees is their egg-shaped cones that hang down from branches.
- Pine Tree Identification by Needles. Pine trees can be easily identified by their needles, which grow in small bundles called fascicles. Each fascicle on pine trees contains two, three, or five needles.
- Soft Needled Pines vs. Hard Needled Pines. An identifying feature of pine trees is whether the needles are soft or hard. Soft needled pines usually have fascicles with five needles, whereas hard needled pines have two or three needles per bundle.
- Types of Pine Trees (with Pictures and Names) – Identification Guide. Let’s look in more detail at some of the most common species of pine trees in the world.
- Eastern White Pine (Pinus strobus) This fast-growing, long-lived pine is one of the most important pine species in North America, grown both for timber and landscape purposes.
- Aleppo Pine (Pinus halepensis) Aleppo pine, sometimes known as Jerusalem pine, is an extremely drought-resistant type of pine tree that is a valuable landscape specimen in hot climates, such as that of southern California.
- Austrian Pine (Pinus nigra) This medium- to large-sized conifer transforms from a pyramidal shape to a rounded-top specimen when fully mature. Also known as European black pine, the Austrian pine can be used as a specimen tree in the landscape or for screening purposes, but it is susceptible to a variety of pest and disease problems, especially in the Midwest.
- Bristlecone Pine (Pinus aristata) This slow-growing, long-lived tree native to the southern Rocky Mountains makes a great specimen tree in the landscape, where its small size is perfect.
Dec 14, 2022 · Pine is a coniferous tree in the genus Pinus, in the family Pinaceae. There are about 111 species of pines worldwide, although different authorities accept between 105 and 125 species. Pines...
Pine refers to any coniferous tree or shrub belonging to the genus Pinus categorized under the family Pinaceae. Pines are found throughout the world, mainly in the northern temperate regions. Although two pine species may look precisely similar, counting the number of needles in each bundle can help identify them.
