slash pine: see pine.

running pine, common name for the plant species Lycopodium clavatum, also called ground pine. See Lycopodiophyta.

prince's pine: see pipsissewa.

pitch pine, common name for the species Pinus rigida, a small pine of the northeastern coastal United States.

pine nut or piñon, edible seed of various species of pine trees. Among the North American species that bear such edible seeds are the nut pines or piñons, Pinus edulis and P. monophylla, and the Digger pine, P. sabiniana, named after the Diggers of California. The nuts have a thin red-brown shell and range in size from about 3/4 in. (1.91 cm) to about 11/2 in. (3.75 cm). Pine nuts, or Indian nuts, were an important food for some early Native Americans and are still harvested in quantity both for food and for trading. They are picked from the ground, taken from squirrel caches, or extracted by hand from the cones. Some pine stands are in danger of depletion because insufficient seeds are left for reproduction. Pignolia nuts are the seeds of P. pinea of S Europe, where they are cultivated and much used for food. Quantities are exported to be used salted and in confectionery. Seeds of numerous other European and Asian pines are gathered under many local names. The name pignolia is often applied to all pine nuts and vice versa.

pine marten: see marten.

pine, common name for members of the Pinaceae, a family of resinous woody trees with needlelike, usually evergreen leaves. The Pinaceae reproduce by means of cones (see cone) rather than flowers and many have winged seeds, suitable for wind distribution. They are found chiefly in north temperate regions, where they form vast forests. The family was apparently more abundant in the mid-Cenozoic era, but it has maintained its population better than other gymnosperms because the trees are more adaptable to cold, dry climates; the reduced leaf surface and deep-set stomata minimize loss of water by transpiration. The family is the largest and most important of the conifers, providing naval stores, paper pulp, and more lumber by far than any other family. In some localities almost pure stands occur, permitting economical lumbering of large numbers of a given type of tree. Of the family's nine genera four are widely dispersed throughout North America and the Old World. Members of all nine genera are represented in horticulture as introduced timber trees or ornamentals. The so-called kauri pine, although pinelike in appearance, belongs to another family (see monkey-puzzle tree).

The True Pines

Pinus (the true pines) is the largest and most widespread genus, characteristic of many north temperate regions (except the plains), especially at lower altitudes, and in a few tropical regions, notably on mountain slopes. Species of Pinus can often be identified by the leaf arrangement, one needle or clusters of from two to five (in all cases enclosed in a sheath at the base) being consistently produced by each type. Many of the pines are economically valuable; from them come the naval stores: pitch (see tar and pitch), turpentine, and rosin. Drying and nondrying oils are also made from the seeds of some pines. Several Mediterranean and American species yield edible seeds (see pine nut).

The ponderosa pine or western yellow pine (P. ponderosa), is a hard pine second only to the Douglas fir as a commercial timber tree in North America. The white pine (P. strobus) has straight-grained soft wood with little resin, used especially for interior trim and cabinetwork. It once grew densely from Newfoundland to Manitoba and over much of the E United States westward to Minnesota, but constant felling and attacks of white-pine blister rust have greatly depleted the stands, especially in the NE United States. The Norway pine, or red pine, (P. resinosa) has a similar range and has also suffered from overcutting. Its wood is somewhat heavier and is suitable for general construction. The Norway pine is frequently used in reforestation programs. The jack pine (P. banksiana), the most northern of the American species, thrives on poor and sandy soils and is much used to colonize areas where more valuable species may later be introduced. Although the trunk is often gnarled, making it unsuitable for good lumber, it supplies much pulpwood and is used locally for rough lumber, fuel, and crating. The Virginia pine (P. virginiana) of the Appalachians and the Piedmont is popular regionally as a Christmas tree. The longleaf pine, or Southern yellow pine (P. palustris) has highly resinous wood used for heavy construction and as a major source of naval stores and pulpwood. It and the faster growing slash pine (P. caribaea) of the same region have gained importance as northern pine stands have been depleted. The latter is widely cultivated in tropical areas with sandy soils. The Scotch pine (P. sylvestris), ranging from Scotland to Siberia and popular as a Christmas tree in the United States, is one of the most valuable timber trees of Europe. The cluster pine (P. pinaster), widespread in S France and in Spain, is the chief European source of turpentine. The Monterey pine (P. radiata) of California has been widely planted in New Zealand and Chile for reforestation.

Other Species in the Pine Family

Abies (fir) species are usually of more northern distribution and found at higher altitudes. Sap-filled "blisters" on the trunks of some species provide balsam. Larix (larch) and Pseudolarix (golden larch, of China) are the only two deciduous genera. Picea (spruce) is the world's most important source of paper. Cedrus (cedar) ranges from the Mediterranean area to the Himalayas; Keteleeria is restricted to E and SE Asia.

Tsuga (hemlock) and Pseudotsuga are native only to North America and E Asia. Pseudotsuga menziesii (the Douglas fir) of W North America, one of the tallest trees known (up to 385 ft/117 m) and the leading timber-producing tree of the continent, is carefully controlled by forestry measures. Its wood, usually hard and strong, is of great commercial importance for construction; it is also commonly used as a Christmas tree in the United States. Named for David Douglas, the tree has many local names, e.g., Douglas spruce, Oregon pine, red fir, and yellow fir.

Classification

Pines are classified in the division Pinophyta, class Pinopsida, order Coniferales.

lodgepole pine, common name for the pine species Pinus contorta, found in the Rocky Mts. and the northwestern coast of the United States.

loblolly pine, common name for the pine species Pinus taeda, found in the SE United States.

ground pine, common name for several creeping plants, particularly species of club moss.

bristlecone pine, common name for the pine species Pinus longaeva, found in the White Mountains of California. Specimens are known that are nearly 5,000 years old.

Wollemi pine, primitive tree, Wollemia nobilis, of the conifer family Araucariaceae, named after Wollemi National Park in New South Wales, Australia, where it was discovered in 1994. Anciently widespread on the supercontinent of Gondwanaland (see plate tectonics), the species was thought to have become extinct at the end of the Cretaceous period (approximately 65 million years ago). Not a true pine, the tree has unusual pale green, fernlike leaves, bright green female cones and brown male cones, and dark brown, corklike bark with a bubbly appearance, and can reach 130 ft (40 m) in height. With fewer than 100 mature trees in two known stands, it is one of the rarest wild plants on earth. To guard against unscrupulous commercial exploitation, the state of New South Wales has trademarked the name, limited access to the wild trees, and developed stock for the nursery market.

Pine Bluff, city (1990 pop. 57,140), seat of Jefferson co., S central Ark., on the Arkansas River; inc. 1839. It is a port and trade center for an agricultural area and has industries producing metal, wood, and paper products; machinery; electrical equipment; and foods. It is also a research center and the seat of the Univ. of Arkansas at Pine Bluff. Of economic importance to the city is the huge Pine Bluff Arsenal to the north; established during World War II, it is the center of U.S. army chemical, biological, and toxicological research. Pine Bluff has an arts and science center and a civic complex designed by Edward Durell Stone.

Pine Barrens, coastal plain region, c.3,000 sq mi (7,770 sq km), S and SE N.J.; composed chiefly of sandy soils, swamp-edged streams, pine stands, and tracts of cranberries and blueberries. Originally a well-forested area of pine, cedar, and oak, its trees were indiscriminately cut for shipbuilding and charcoal-making until the 1860s, when they were nearly exhausted. A second growth of pine was of poor quality, and most of the region, except for scattered stands, remained bare. Several state forests and Fort Dix, a U.S. army base, are there. On the periphery of the Pine Barrens, suburban development has grown since the 1970s. Efforts to maintain the wilderness have increased as a result of environmentalist action, but such projects remain difficult. There is also a Pine Barrens on Long Island in New York.

Norfolk Island pine: see monkey-puzzle tree.

Any of 10 genera of coniferous trees (rarely shrubs) of the family Pinaceae (see conifer), native to northern temperate regions, especially about 90 species of ornamental and timber evergreen conifers of the genus Pinus. Needlelike leaves and cones are solitary or in bunches. Shallow root systems make pines susceptible to wind and surface disturbance. The family includes fir, Douglas fir, hemlock, spruce, larch, and cedar. Many species are sources of softwood timber, paper pulp, oils, and resins. Some are cultivated as ornamentals.

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Any of about 200 species of primitive vascular plants that constitute the genus Lycopodium (order Lycopodiales), mainly native to tropical mountains but also common in northern forests of both hemispheres. They are evergreen plants with needlelike leaves and, often, conelike clusters of small leaves (strobili; see cone), each with a kidney-shaped spore capsule at its base. Representative species include running pine, or stag's horn moss (L. clavatum), ground cedar (L. complanatum ‘flabelliforme'), shining club moss (L. lucidulum), fir club moss (L. selago), ground pine (L. obscurum), and alpine club moss (L. alpinum).

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Evergreen timber and ornamental conifer (Araucaria excelsa, or A. heterophylla) of the family Araucariaceae, native to Norfolk Island in the South Pacific Ocean. In nature this pine grows to a height of 200 ft (60 m), with a trunk sometimes reaching 10 ft (3 m) in diameter. The wood of large trees is used in construction, furniture, and shipbuilding. The sapling stage is grown worldwide as a houseplant and as an outdoor ornamental in regions with a Mediterranean climate. The monkey puzzle tree is a relative.

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