In the genus Pinus, there are approximately 115 recognized species of pine. The largest and most widespread of trees, this genus is characteristic of many north temperate regions, especially at lower altitudes. The pines are divided into three subgenera based on cone, seed, and leaf characters: Pinus pinus- yellow or hard pine, Pinus ducampopinus-foxtail or pinyon, and Pinus strobus-white or soft. Native to most of the Northern hemisphere, the pine been introduced throughout most temperate and subtropical regions of the world, where they are grown as timber and cultivated as ornamental plants in parks and gardens.
The majority of the species of pine reach between 50 and 150 ft (15-45 m) tall. The tallest is a 268 ft tall Ponderosa Pine located in southern Oregon. Pines are long-lived, typically reaching ages of 100-1,000 years or more. One of the world’s oldest living organisms is a species of pine, dubbed Methuselah, which is dated at around 4,600 years old in the White Mountains of California. The pines are distinguished from other needle-leaved and coniferous evergreens, by the papery, enclosing sheath at the base of their needle clusters. Nearly one half of the 115 known species of pine grow in North America. Among them are pines for every situation, soil and climate. They wade in inundated swamps and climb to the timberline on arid, rocky mountainsides. Found in harsh deserts and seaboard plains; as shelterbelts, windbreaks, and for the production of naval stores, these trees are as useful as they are adaptable.
Pines grow well in acid soils, some also on soil where lime is heavily present. Most require good soil drainage, preferring sandy terrain. Several species are adapted to extreme conditions imposed by elevation and latitude, and a few require fire to regenerate. Among the most commercially important species of tree, they are valued for timber and wood pulp throughout the world. In temperate and tropical regions they are fast growing softwoods that thrive in relatively dense stands. Commercial pines are grown in plantations for timber that is denser, more resinous, and therefore more durable than spruce. Widely used in high-value carpentry items such as furniture, window frames, paneling, floors and roofing. The resin of some species is an important resource in the manufacturing of soap, paint, varnish, shoe polish, lubricants, and linoleum.
The Ponderosa, or Western Yellow Pine (P. radiata) is a hard pine, second only to the Douglas Fir as a main provider for commercial timber in North America. White Pine (P. strobes) has straight-grained soft wood with little resin, especially for interior trim and cabinetry. Once growing in dense strands from Newfoundland to Manitoba and over much of the eastern United States, forests have been depleted due to constant felling and White Pine blister rust.
The branches of the pine are produced in regular “pseudo whorls,” a very tight spiral but appearing like a ring of branches arising from the same point. Many pines are uniodal, producing just one such whorl a year. The spiral growth of branches, needles and cone scales are arranged in Fibonacci number ratios. Beneath most of those scales are contained small seeds; many species of pine produce these with wings suited for wind-dispersal.
The division of the pines is a convenient one, “soft pines” have soft, close-grained, light wood that is not heavily imbued with resin. The scales of cones are usually unarmed with horns or prickles. “Hard pines” have heavy, dark-coloured wood, full of resin and armored cones. Soft pines shed the characteristic papery sheath of their leaf bundles before the leaves themselves begin to drop. Hard pines retain the leaf sheath until the leaves are shed.
Longleaf Pine Pinus palustris
Native to the southeastern United States, this species of pine is found along the coastal plain from Texas to Virginia, and down into Florida where vast forests once stood as part of the eastern savannas. Seedlings resemble a green fountain of needles and can stay in this diminutive form for 5 to 12 years. It takes 100 to 150 to become a full size tree and may live up to 500 years. It reaches heights of 98-155 ft (30-35 m) and roughly two feet in diameter. This species of pine is very important to the production of timber. As it is rather resinous, the heartwood of this pine is resistant to rot and termites.
White Pine Pinus strobes
The only pine east of the Rocky Mountains that bears its leaves in bundles of five, this semi-decimal growth pattern is shared with five western species. Before storms have broken any of the branches and disrupted the pattern the branching platforms of five are easily distinguished. In spring the terminal bud pushes out and is surrounded by five clustering buds forming a circle of shoots. In autumn, after season’s growth is finished, each twig ends in a single bud, with a whorl of five buds around it. Each whorl of five marks a year in the tree’s growth. Each branch is a year younger than the shoot that bears it. This tree is biennial-fruited, always carrying two sizes of cones. Ripe ones are five to ten inches long, with thin, broad, unarmed scales. The wood is lightweight, soft, even-textured and easily worked as it is the least resinous of all pines. It is straight grained with a fine, uniform texture that acquires an amber patina with age.
Mountain Pine Pinus monticola
The Mountain Pine is scattered through mountain forests along the western slopes of the Rocky Mountains, and south along the Sierra Nevada and Cascade ranges, well into California. From the bottom lands of streams where it is most prevalent, reaching heights of 100 to 150 ft, it is also found in elevations of eight to ten thousand feet in the California Sierras. The leaves are contained in bundles of five, range from one to four inches in length. The cones are 12-18 inches long, with thickened, pointed scales ending in an abrupt beak. Where most trees would begin to diminish in size as altitude increases, these pines grow to majestic heights at altitudes of nearly two miles.
Sugar Pine Pinus lambertiana
Growing in the mountain forests of Oregon and California, John Muir calls it “the largest, noblest, and most beautiful of all the pine trees.” Trees two hundred feet high are not uncommon, with trunk diameters of 6-8 ft. the head of a Sugar Pine is rounded and broad, with pendulous branches, tufted with stout, dark green needles. The cones are the largest known, reaching 18 inches long. Crystals of sugar form white masses like rock candy wherever a break in the bark permits the escape of sweet sap. The wood of the Sugar Pine is soft, golden, satiny, and fragrant, inviting in every sense.
Rocky Mountain White Pine Pinus flexilis
The lumber pine of the semi-arid ranges of the “Great American Dessert”, this pine inhabits mountain slopes from Alberta to Mexico, including the Sierra Nevada range. It can reach 80 feet in height, although it ordinarily does not exceed 50. Its broad, rounded dome, bravely dares the wind on exposed cliffs. The “limber pine” a common moniker, as the toughness of its fiber enables the long limbs to sustain the thrashing of winds.