''Pinus strobiformis'', commonly known as southwestern white pine, Mexican white pine or Chihuahua white pine, is a medium-sized

white pine ''Pinus'', the pines, is a genus of approximately 111 extant tree and shrub species. The genus is currently split into two subgenera: subgenus ''Pinus'' (hard pines), and subgenus ''Strobus'' (soft pines). Each of the subgenera have been furth ...

tree whose native habitat is in southwestern United States and Mexico. It is typically a high-elevation pine growing mixed with other

conifers Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All exta ...

(a montane forest).

Description

''Pinus strobiformis'', a member of the

group, ''

Pinus A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family (biology), family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanic ...

'' subgenus '' Strobus'', is a straight, slender tree growing to 30 m tall and 1 m in diameter. The

bark Bark may refer to: * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Places * Bark, Germany * Bark, Warmian-Masurian Voivodeship, Poland Arts, e ...

is smooth and silvery-gray on young trees, aging to furrowed and red-brown or dark gray-brown. The branches are spreading and ascending. Twigs are slender, pale red-brown, aging to smooth gray or gray-brown. Buds are ellipsoid, red-brown, and resinous.

Leaves A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...

(needles) are five per bundle ( fascicle), sometimes four, spreading to ascending-upcurved, 4–9 cm long (rarely 10), 0.6-1.0 mm in diameter, straight, slightly twisted, pliant, dark green to blue-green, and persist 3–5 years. The upper surface ('adaxial' - facing toward the stem of the plant) is conspicuously whitened by narrow

stomatal In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bor ...

lines. The lower surfaces ('abaxial' - facing away from the stem of the plant) are without evident stomatal lines. The margins are sharp, razorlike and entire to finely serrulate, apex narrowly acute to short-subulate. Each fascicle has a deciduous sheath 1.5-2.0 cm long which is shed early. The cones are very large, 16–50 cm long and 9–11 cm broad, and have scales with a very characteristic prolonged and often recurved or S-shaped apex. The seeds are large, and with a very short wing; they are dispersed mainly by birds, particularly the

Mexican jay The Mexican jay (''Aphelocoma wollweberi'') Etymology: ''Aphelocoma'', from Latinized Ancient Greek ''apheles-'' (from ἀφελής-) "simple" + Latin ''coma'' (from Greek ''kome'' κόμη) "hair", in reference to the lack of striped or bande ...

. It is a very drought tolerant tree but greater populations grow on moist and cool places living in association with ''

Pinus hartwegii ''Pinus hartwegii'' ( syn. ''P. rudis'', ''P. donnell-smithii''), Hartweg's pine or pino de las alturas, is a pine native to the mountains of Mexico and Central America east to Honduras. It is named after Karl Theodor Hartweg, who described it i ...

''.

Distribution

The tree can natively be found in mountainous areas in Arizona, southwest

Colorado Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the ...

, New Mexico, and western Texas. Most of the native pines are in Mexico, in the

Sierra Madre Occidental The Sierra Madre Occidental is a major mountain range system of the North American Cordillera, that runs northwest–southeast through northwestern and western Mexico, and along the Gulf of California. The Sierra Madre is part of the American Co ...

mountains of northern Mexico, from a short distance south of the US–Mexico border south through

Chihuahua Chihuahua may refer to: Places * Chihuahua (state), a Mexican state **Chihuahua (dog), a breed of dog named after the state **Chihuahua cheese, a type of cheese originating in the state **Chihuahua City, the capital city of the state **Chihuahua Mu ...

and

Durango Durango (), officially named Estado Libre y Soberano de Durango ( en, Free and Sovereign State of Durango; Tepehuán: ''Korian''; Nahuatl: ''Tepēhuahcān''), is one of the 31 states which make up the 32 Federal Entities of Mexico, situated in ...

Jalisco Jalisco (, , ; Nahuatl: Xalixco), officially the Free and Sovereign State of Jalisco ( es, Estado Libre y Soberano de Jalisco ; Nahuatl: Tlahtohcayotl Xalixco), is one of the 31 states which, along with Mexico City, comprise the 32 Federal En ...

. The pine rarely appears in pure strands, but grows along with other native conifers, such as limber pine, ponderosa pine,

blue spruce The blue spruce (''Picea pungens''), also commonly known as green spruce, Colorado spruce, or Colorado blue spruce, is a species of spruce tree. It is native to North America, and is found in USDA growing zones 1 through 7. It is found naturally ...

aspen Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the '' Populus'' genus. Species These species are called aspens: *'' Populus adenopoda'' – Chinese aspen (C ...

white fir ''Abies concolor'', the white fir, is a coniferous tree in the pine family Pinaceae. This tree is native to the mountains of western North America, including the Cascade Range and southern Rocky Mountains, and into the isolated mountain ranges ...

, Douglas fir, and

Engelmann spruce ''Picea engelmannii'', with the common names Engelmann spruce, white spruce, mountain spruce, and silver spruce, is a species of spruce native to western North America. It is mostly a high-altitude mountain tree but also appears in watered canyon ...

Uses

The southwestern white pine can be grown as a

Christmas tree A Christmas tree is a decorated tree, usually an evergreen conifer, such as a spruce, pine or fir, or an artificial tree of similar appearance, associated with the celebration of Christmas. The custom was further developed in early modern G ...

windbreak A windbreak (shelterbelt) is a planting usually made up of one or more rows of trees or shrubs planted in such a manner as to provide shelter from the wind and to protect soil from erosion. They are commonly planted in hedgerows around the edges ...

tree, or an ornamental tree. It is popular as a replacement in drier areas for the eastern white pine. It can be used in cabinet making, but it is poor as a lumber tree. The seeds were used as a food by Native Americans in the present day southwestern United States.

References

External links

''Pinus strobiformis'' cone pics; compare also ''Pinus reflexa'' and ''Pinus flexilis'' (scroll ¼ way down page)
*http://www.pinetum.org/articles/Pinus/PNstylesiiFrankis2009.pdf *http://www.coloradotrees.org/feature_trees/pine_sw.php {{Authority control strobiformis Pinus strobiformis Pinus strobiformis Pinus strobiformis Pinus strobiformis Edible nuts and seeds Plants used in Native American cuisine Pinus strobiformis Flora of the Sierra Madre Occidental