''Pinus leiophylla'', commonly known as Chihuahua pine, smooth-leaf pine,''Pinus leiophylla'' was originally described and published in ''Linnaea'' 6:354. 1831. and yellow pine (in

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

, tlacocote and ocote chino), is a

tree In botany, a tree is a perennial plant with an elongated Plant stem, stem, or trunk (botany), trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondar ...

with a range primarily in Mexico, with a small extension into the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territo ...

in southeast Arizona and southwest

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

. The Mexican range extends along 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 ...

and

Sierra Madre del Sur The Sierra Madre del Sur is a mountain range in southern Mexico, extending from southern Michoacán east through Guerrero, to the Isthmus of Tehuantepec in eastern Oaxaca. Geography The Sierra Madre del Sur joins with the Eje Volcánico Transv ...

from Chihuahua to Oaxaca, from 29° North Lat. to 17°, between 1600 and 3000 meters altitude. It requires about a rainfall 600 to 1000 mm a year, mostly in summer. It tolerates frosts in winter.

Description

This member of family

Pinaceae The Pinaceae, or pine family, are conifer trees or shrubs, including many of the well-known conifers of commercial importance such as cedars, firs, hemlocks, larches, pines and spruces. The family is included in the order Pinales, formerly know ...

grows to the height of with a trunk diameter of . The needles are in bundles of three to five, long, or rarely to , and are a bright glossy green to yellowish-green. The cones are ovoid, long, or rarely to , and borne on a long stalk; they are unusual in taking about 30–32 months to mature, a year longer than most other

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

s. The bark is gray-brownish, and fissured.

Subspecies

There are two subspecies (treated by some botanists as distinct species, by others as just varieties): *''Pinus leiophylla'' subsp. ''leiophylla''. Needles slender (0.5–0.9 mm), in fives. It occurs in the southern part of the range, from Oaxaca to

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 ...

, is not frost tolerant, and grows in relatively high rainfall conditions. *''Pinus leiophylla'' subsp. ''chihuahuana''. Needles stouter (0.9–1.3 mm), in threes. It occurs in the northern part of the range, from Durango to Arizona, tolerates frost down to about −10 °C to −15 °C, and very dry conditions. The needle differences are adaptations to these harsher conditions. Synonyms ''Pinus chihuahuana'', ''Pinus leiophylla'' var. ''chihuahuana''.

Habitat and ecology

This species often grows in mixed in stands with several other pines and/or

juniper Junipers are coniferous trees and shrubs in the genus ''Juniperus'' () of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere, from the Arcti ...

s, in Arizona most often with

Apache Pine ''Pinus engelmannii'', commonly known as the Apache pine, is a tree of Northern Mexico, in the Sierra Madre Occidental with its range extending a short distance into the United States in southwestern New Mexico and southeastern Arizona. This pin ...

and Alligator Juniper, but also grows in pure stands. Its habitat is prone to wildfire, and the species shows some adaptations unusual among pines to cope with this; if the crown is destroyed by fire, the trunk, protected by its thick bark, will send out new shoots to re-grow a new crown. The only other pines to do this are

Pitch Pine ''Pinus rigida'', the pitch pine, is a small-to-medium-sized pine. It is native to eastern North America, primarily from central Maine south to Georgia and as far west as Kentucky. It is found in environments which other species would find unsuit ...

(''P. rigida'') and Canary Island Pine (''P. canariensis''). As none of these are species particularly closely related to each other, the adaptation has probably arisen independently in each, an example of convergent evolution.

Cultivation and uses

The wood of the ''Pinus leiophylla'' is hard, dense and strong. It is used for construction, firewood, and railroad ties. In

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

and

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

, Australia there are big extensions of this tree planted. It is planted commercially in

Kenya ) , national_anthem = " Ee Mungu Nguvu Yetu"() , image_map = , map_caption = , image_map2 = , capital = Nairobi , coordinates = , largest_city = Nairobi ...

Malawi Malawi (; or aláwi Tumbuka: ''Malaŵi''), officially the Republic of Malawi, is a landlocked country in Southeastern Africa that was formerly known as Nyasaland. It is bordered by Zambia to the west, Tanzania to the north and northeast ...

Zimbabwe Zimbabwe (), officially the Republic of Zimbabwe, is a landlocked country located in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Botswana to the south-west, Zambia to the north, and Mozam ...

Zambia Zambia (), officially the Republic of Zambia, is a landlocked country at the crossroads of Central, Southern and East Africa, although it is typically referred to as being in Southern Africa at its most central point. Its neighbours are t ...

at high altitudes.

References

External links

County Distribution in Arizona
from plants.usda.gov
County Distribution in New Mexico
from plants.usda.gov
Interactive Distribution Map of ''Pinus leiophylla''
from plantmaps.com {{Taxonbar, from=Q2737854 leiophylla Trees of Mexico Trees of Oaxaca Trees of Puebla Trees of the Southwestern United States Trees of Durango Trees of Chihuahua (state) Trees of the South-Central United States Flora of Northeastern Mexico Plants described in 1831 Trees of temperate climates Drought-tolerant trees Least concern plants Flora of the Sierra Madre Occidental Flora of the Sierra Madre del Sur Flora of the Trans-Mexican Volcanic Belt