''Pinus nelsonii'', Nelson's pinyon, is a species of

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. ''World Flora Online'' accepts 134 species-rank taxa (119 species and 15 nothospecies) of pines as cu ...

native to the mountains of northeastern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

, in

Nuevo León Nuevo León, officially the Free and Sovereign State of Nuevo León, is a Administrative divisions of Mexico, state in northeastern Mexico. The state borders the Mexican states of Tamaulipas, Coahuila, Zacatecas, and San Luis Potosí, San Luis ...

San Luis Potosí San Luis Potosí, officially the Free and Sovereign State of San Luis Potosí, is one of the 32 states which compose the Federal Entities of Mexico. It is divided in 59 municipalities and is named after its capital city, San Luis Potosí. It ...

and

Tamaulipas Tamaulipas, officially the Free and Sovereign State of Tamaulipas, is a state in Mexico; one of the 31 states which, along with Mexico City, comprise the 32 federal entities of Mexico. It is divided into 43 municipalities. It is located in nor ...

at 1,800–3,200 m altitude.

Description

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'' from the western

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

. The needles are produced in fascicles of three (occasionally four), but 'zipped' together by their finely serrated margins so that they look like a single needle; they 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 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 In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

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.Farjon, A. & Styles, B. T. (1997). Pinus (Pinaceae). ''Flora Neotropica'' Monograph 75. The

s are edible and delicious, and are very appreciated by people in the region. They are so valuable that they are transported to the markets of

Mexico City Mexico City is the capital city, capital and List of cities in Mexico, largest city of Mexico, as well as the List of North American cities by population, most populous city in North America. It is one of the most important cultural and finan ...

. 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''. File:Pinus nelsonii (Nelson's Pinyon) (31179779021).jpg, ''Pinus nelsonii'' foliage File:Pinus nelsonii, General Zaragoza, Nuevo León, Mexico 1.jpg, Cones File:Pinus nelsonii, General Zaragoza, Nuevo León, Mexico 2.jpg, Seeds

Systematics

It has very singular characteristics and is not closely related to any other pines in either morphologyShaw, G. R. (1904). Pinus nelsonii. ''Gard. Chron''. ser.3, 36: 122, f.49.Grimshaw, J., & Bayton, R. (2009). ''New Trees''. International Dendrology Society / Kew. . 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."

References

{{Taxonbar, from=Q3308389 nelsonii Edible nuts and seeds Trees of Northern America Drought-tolerant trees Flora of the Sierra Madre Oriental Taxa named by George Russell Shaw