''Pinus maximartinezii'', called Martinez pinyon, big-cone pinyon
[ or maxipiñon,]
Description
It is a small tree, reaching tall and with a trunk diameter of up to . The bark is brown, thick and fissured at the base of the trunk. The leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
('needles') are in fascicles of five, slender, long, and deep green to blue-green, with stomata
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 ...
confined to a bright white band on the inner surfaces. The cones are ovoid, massive, long and broad and up to weight when closed, green at first, ripening yellow-brown when 26–28 months old, with very thick, woody scales, typically 30–60 fertile scales. The scales are unusual for a pine in the soft 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 further ...
group (''Pinus'' subgenus ''Strobus''); most pines in that group have flexible scales. The cones open to broad when mature. The seeds are long, with a thick shell, with a vestigial wing; the seedlings have 18–24 cotyledons, the highest number reported for any plant.
It differs from all other pinyon species in that it has very massive cones and large seeds. Like other pinyons, the seeds are edible; this represents a threat to the species' survival, as the majority of the seeds produced are harvested, limiting natural regeneration of the pines.
Range and habitat
The range is highly localised, confined to two small areas of the southern Sierra Madre Occidental – the Sierra de Morones in southern Zacatecas, and La Muralla in 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 ...
. It occurs at moderate altitudes, from 1800–2400 m and 21° North latitude, in warm and temperate, dry climate conditions.
The Mexican government has declared this species endangered.
Discovery
Because of its isolation in a remote area, it escaped discovery until 1964, when the Mexican botanist Jerzy Rzedowski noticed some unusually large pine nuts (''piñones'') sold in the markets of local villages, and investigated the area to find their source.
Cultivation
It has started being cultivated recently and is a very attractive ornamental tree.
References
External links
Gymnosperm Database: ''Pinus maximartinezii''
*Farjon, A. & Styles, B. T. (1997). Pinus (Pinaceae). ''Flora Neotropica Monograph'' 75: 221–224.
Conifers Around the World: ''Pinus maximartinezii – Martínez Pinyon Pine''
{{Taxonbar, from=Q3308307
maximartinezii
Edible nuts and seeds
Endangered plants
Endemic flora of Mexico
Flora of the Sierra Madre Occidental