Pinus nelsonii
Encyclopedia
Pinus nelsonii is a species of pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

 native to the mountains of northeastern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

, in Nuevo León
Nuevo León
Nuevo León It is located in Northeastern Mexico. It is bordered by the states of Tamaulipas to the north and east, San Luis Potosí to the south, and Coahuila to the west. To the north, Nuevo León has a 15 kilometer stretch of the U.S.-Mexico border adjacent to the U.S...

, San Luis Potosí
San Luis Potosí
San Luis Potosí officially Estado Libre y Soberano de San Luis Potosí is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 58 municipalities and its capital city is San Luis Potosí....

 and Tamaulipas
Tamaulipas
Tamaulipas officially Estado Libre y Soberano de Tamaulipas is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 43 municipalities and its capital city is Ciudad Victoria. The capital city was named after Guadalupe Victoria, the...

 at 1,800–3,200 m altitude. It has very singular characteristics and is not closely related to any other pines in either morphology or genetics. It is placed in subgenus Strobus either in its own section Nelsonia or subsection Nelsoniae.
"Pinus nelsonii is exceptional. Evidence from three nuclear genes (Syring et al., 2005) and cpDNA (Gernandt et al., 2005) resolve P. nelsonii as sister lineage to the remaining members of sect. Parrya. In contrast, the LEA-like locus used in this study places P. nelsonii in a unique, moderately supported (71% BS) position sister to sect. Quinquefoliae when midpoint rooting is employed."


It is a small tree growing to 10 m tall with a trunk up to 20–30 cm diameter. The crown is rounded and dense, and resembles that of the unrelated Pinus pinea
Stone Pine
The Stone Pine , is also called Italian Stone Pine, or Umbrella Pine , and Parasol Pine. It is in the pine family Pinaceae and occasionally listed under the invalid name Pinus sativa. The tree is native to the Mediterranean region...

from the western Mediterranean
Mediterranean Basin
In biogeography, the Mediterranean Basin refers to the lands around the Mediterranean Sea that have a Mediterranean climate, with mild, rainy winters and hot, dry summers, which supports characteristic Mediterranean forests, woodlands, and scrub vegetation...

. The needles are produced in fascicles of three (occasionally four), but 'zipped' together in apparent single fascicles which can only be separated by force. They are 4–8 (rarely 10) cm long and 0.7–1 mm thick, sub-shiny dark green in colour, with a persistent grey basal sheath 7–9 mm long. The cones
Conifer cone
A cone is an organ on plants in the division Pinophyta that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity...

 are cylindrical, 6–12 cm long and 4–5 cm broad, orange-brown to red-brown colour, with 60–100 scales with large but indistinct umbos, and carried on a stout downcurved peduncle 3–6 cm long. Unlike all other pines, their growth while immature does not pause during the first winter. The seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

s are large, 12–15 mm, red-brown. The cones mature in November after rain season. It grows in a semi-arid temperate climate with summer rainfall and is very drought-tolerant.

The seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

s are edible and delicious and are very appreciated by people in the region and are so valuable that they are transported to the markets of Mexico City
Mexico City
Mexico City is the Federal District , capital of Mexico and seat of the federal powers of the Mexican Union. It is a federal entity within Mexico which is not part of any one of the 31 Mexican states but belongs to the federation as a whole...

. Because of its seeds it has been very devastated by people. Only recently it has been cultivated outside its native range, grown more for its botanical curiosity than for ornamental values.

The scientific name is occasionally cited incorrectly as Pinus nelsoni; the correct ending is -ii.
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