Pine

Pines are coniferous trees of the genus Pinus, in the family Pinaceae. There are about 115 species of pine, although different authors accept anything between about 105 to 125 species.

They are native to most of the Northern Hemisphere. In North America, they range from the Arctic south to Nicaragua and Hispaniola, with the highest diversity in Mexico and California. In Eurasia, they range from Spain and Scotland east to the Russian Far East, Japan, and the Philippines, and south to northernmost Africa, the Himalaya and Southeast Asia, with one species (Sumatran Pine) just crossing the Equator in Sumatra. Pines are also extensively planted in many parts of the Southern Hemisphere.

Pines are evergreen and resinous. The bark of most pines is thick and scaly, but some species have thin, flaking bark. The branches are produced in regular "pseudowhorls", actually a very tight spiral but appearing like a ring of branches arising from the same point. Many pines are uninodal, producing just one such whorl of branches each year, from buds at the tip of the year's new shoot, but others are multinodal, producing two or more whorls of branches per year. The new spring shoots are sometimes called "candles"; they are light-colored and point upward at first, later darken and spreading outward. These "candles" offer foresters a means to evaluate fertility of the soil and/or vigour of the trees.

Pines have four types of leaves. Seedlings begin with (1) a whorl of 4-20 seed leaves (cotyledons), followed immediately by (2) juvenile leaves on young plants, 2-6 cm long, single, green or often blue-green, and arranged spirally on the shoot. These are replaced after six months to five years by (3) scale leaves, similar to bud scales, small, brown and non-photosynthetic, and arranged like the juvenile leaves; and (4) the adult leaves or needles, green (photosynthetic), bundled in clusters (fascicles) of (1-) 2-5 (-6) needles together, each fascicle produced from a small bud on a dwarf shoot in the axil of a scale leaf. These bud scales often remain on the fascicle as a basal sheath. The needles persist for 1.5-40 years, depending on species. If a shoot is damaged (e.g. eaten by an animal), the needle fascicles just below the damage will generate a bud which can then replace the lost growth.

Pines are monoecious, having the male and female cones on the same tree. The male cones are small, typically 1-5 cm long, and only present for a short period (usually in spring, though autumn in a few pines), falling as soon as they have shed their pollen. The female cones take 1.5-3 years (depending on species) to mature after pollination, with actual fertilization delayed one year. At maturity the cones are 3-60 cm long. Each cone has numerous spirally arranged scales, with two seeds on each fertile scale; the scales at the base and tip of the cone are small and sterile, without seeds. The seeds are mostly small and winged, and are anemophilous (wind-dispersed), but some are larger and have only a vestigial wing, and are bird-dispersed (see below). At maturity, the cones usually open to release the seeds, but in some of the bird-dispersed species (e.g. Whitebark Pine), the seeds are only released by the bird breaking the cones open. In others, the fire climax pines, the seeds are stored in closed cones for many years until a forest fire kills the parent tree; the stored seeds are then released in huge numbers to re-populate the burnt ground.

The spiral growth of branches, needles and cone scales are arranged in Fibonacci number ratios.

Pines grow well in acid soils, some also on calcareous soils; most require good soil drainage, preferring sandy soils, but a few, e.g. Lodgepole Pine, will tolerate poorly drained wet soils. A few are able to sprout after forest fires, e.g. Canary Island Pine. Some species of pines, e.g. Bishop Pine, need fire to regenerate and their populations slowly decline under fire suppression regimes. Several species are adapted to extreme conditions imposed by elevation and latitude; see e.g. Siberian Dwarf Pine, Mountain Pine, Whitebark Pine and the bristlecone pines.

The seeds are commonly eaten by birds and squirrels. Some birds, notably the Spotted Nutcracker, Clark's Nutcracker and Pinyon Jay, are of importance in distributing pine seeds to new areas where they can grow.

Uses

Pines are commercially among the most important of species used for timber in temperate and tropical regions of the world. Many are grown as a source of wood pulp for papermaking. This is because they are fast-growing softwoods that can be planted in relatively dense stands, and because their acidic decaying needles may inhibit the growth of other competing plants in the cropping areas. A typical example is Pinus radiata. The resin of some species is important as the source of turpentine. Some species have large seeds, called pine nuts, that are harvested and sold for cooking and baking. Some pines are used for christmas trees, and pine cones are also widely used for christmas decorations. Many pines are also very attractive ornamental trees planted in parks and large gardens. A large number of dwarf cultivars have been selected, suitable for planting in smaller gardens.

Pine plantations can be at risk of fire damage because pine resin is flammable to the point of a tree being explosive under some conditions.

Name origins

The modern English name pine derives from Latin Pinus by way of French pin. In the past (pre-19th century) they were often known as fir, from Old Norse fyrre, by way of Middle English firre. The Old Norse name is still used for pines in some modern north European languages: in Danish, fyr, in Nowegian, furu, and Föhre in parts of Germany, but in modern English, "fir" is now restricted to Abies and Pseudotsuga. Other unrelated European names include German Kiefer (the most widely used name in Germany), Swedish tall, Dutch den, Finnish mänty, Russian sosna, Bulgarian and Serbo-Croat bor, and Greek pitys.

Classification of Pinus (under construction)

List of pines by region

North American pine species:

(i) Canada & USA, except for close to the Mexican border:

• Whitebark Pine - P. albicaulis
• Rocky Mountains Bristlecone Pine - P. aristata
• Knobcone Pine - P. attenuata
• Foxtail Pine - P. balfouriana
• Jack Pine - P. banksiana
• Sand Pine - P. clausa
• Lodgepole Pine - P. contorta
• Coulter Pine - P. coulteri
• Shortleaf Pine - P. echinata
• Colorado Pinyon - P. edulis
• Slash Pine - P. elliottii
• Limber Pine - P. flexilis
• Spruce Pine - P. glabra
• Jeffrey Pine - P. jeffreyi
• Sugar Pine - P. lambertiana
• Great Basin Bristlecone Pine - P. longaeva
• Single-leaf Pinyon - P. monophylla
• Western White Pine - P. monticola
• Bishop Pine - P. muricata
• Longleaf Pine - P. palustris
• Ponderosa Pine - P. ponderosa, including P. washoensis
• Table Mountain Pine - P. pungens
• Monterey Pine - P. radiata
• Southwestern White Pine - P. reflexa
• Texas Pinyon or Papershell Pinyon - P. remota
• Red Pine - P. resinosa
• Pitch Pine - P. rigida
• Gray Pine, Foothill Pine or Digger Pine, P. sabineana
• Pond Pine - P. serotina
• Eastern White Pine - P. strobus
• Loblolly Pine - P. taeda
• Torrey Pine - P. torreyana
• Virginia Pine - P. virginiana

(ii) Southern Arizona & New Mexico, Mexico, Central America & Caribbean:

• Apulco Pine - P. apulcensis
• Arizona Pine - P. arizonica
• Mexican White Pine - P. ayacahuite
• Caribbean Pine - P. caribaea
• Mexican Pinyon - P. cembroides
• Chiapas White Pine - P. chiapensis
• Cooper's Pine - P. cooperi
• Cuban Pine - P. cubensis
• Potosí Pinyon - P. culminicola
• Michoacan Pine - P. devoniana (syn. P. michoacana)
• Durango Pine - P. durangensis
• Apache Pine - P. engelmannii
• Estevez's Pine - P. estevezii
• Gordon's Pine - P. gordoniana (syn. P. douglasiana)
• Gregg's Pine - P. greggii
• Hartweg's Pine - P. hartwegii
• Herrera's Pine - P. herrerae
• Honduras Pine - P. hondurensis (syn. P. caribaea var. hondurensis)
• Jalisco Pine - P. jaliscana
• Johann's Pinyon - P. johannis
• Lawson's Pine - P. lawsonii
• Chihuahua Pine - P. leiophylla
• Lumholtz's Pine - P. lumholtzii
• Big-cone Pinyon - P. maximartinezii
• Thinleaf Pine - P. maximinoi (syn. P. tenuifolia)
• Montezuma Pine - P. montezumae
• Nelson's Pinyon - P. nelsonii
• Hispaniolan Pine - P. occidentalis
• Egg-cone Pine - P. oocarpa
• Patula Pine - P. patula
• Orizaba Pinyon - P. orizabensis
• Weeping Pinyon - P. pinceana
• McVaugh's Pine - P. praetermissa
• Pringle's Pine - P. pringlei
• Smooth-bark Mexican Pine - P. pseudostrobus
• Parry Pinyon - P. quadrifolia
• Rzedowski's Pine - P. rzedowskii
• Chihuahua White Pine - P. strobiformis
• Tecun Uman Pine - P. tecunumanii
• Ocote Pine - P. teocote
• Tropical Pine - P. tropicalis

European & Mediterranean pine species (some extend into Asia):

• Turkish Pine - P. brutia
• Canary Island Pine - P. canariensis
• Swiss Pine - P. cembra
• Aleppo Pine - P. halepensis
• Bosnian Pine - P. heldreichii
• Mountain Pine - P. mugo
• European Black Pine or Austrian pine - P. nigra
• Macedonian Pine - P. peuce
• Maritime Pine - P. pinaster
• Stone Pine - P. pinea
• Scots Pine - P. sylvestris

Asian pine species:

• Yakushima White Pine - P. amamiana
• Chinese White Pine - P. armandii
• Bhutan White Pine - P. bhutanica
• Lacebark Pine - P. bungeana
• Vietnamese White Pine - P. dalatensis
• Sikang Pine - P. densata
• Japanese Red Pine - P. densiflora
• Hainan White Pine - P. fenzeliana
• Chilgoza Pine - P. gerardiana
• Henry's Pine - P. henryi
• Huangshan Pine - P. hwangshanensis
• Khasi Pine - P. kesiya
• Korean Pine - P. koraiensis
• Krempf's Pine - P. krempfii
• Tenasserim Pine - P. latteri
• Luchu Pine - P. luchuensis
• Masson's Pine - P. massoniana
• Sumatran Pine - P. merkusii
• Taiwan White Pine - P. morrisonicola
• Japanese White Pine - P. parviflora
• Siberian Dwarf Pine - P. pumila
• Chir Pine - P. roxburghii
• Siberian Pine - P. sibirica
• Qiaojia Pine - P. squamata
• Chinese Red Pine - P. tabuliformis
• Taiwan Red Pine - P. taiwanensis
• Japanese Black Pine - P. thunbergii
• Blue Pine - P. wallichiana
• Guangdong White Pine - P. wangii (syn. P. kwangtungensis)
• Yunnan Pine - P. yunnanensis

References

• Richardson, D. M. (ed.). 1998. Ecology and Biogeography of Pinus. Cambridge University Press, Cambridge. 530 p. ISBN 0-521-55176-5
• Mirov, N. T. 1967. The Genus Pinus. Ronald Press, New York (out of print).
• Farjon, A. 1984. Pines. E. J. Brill, Leiden. ISBN 90-04-07068-0

External links

• Classification of pines
• Arboretum de Villardebelle Images of cones of selected species
• Gymnosperm Database - Pinus
• Gymnosperm families - scroll down to the Pinaceae

Links to other Pinaceae

Pinus - Picea - Cathaya - Larix - Pseudotsuga - Abies - Cedrus - Keteleeria - Pseudolarix - Nothotsuga - Tsuga

See also: Pine email client.