Big-cone Pinyon
Encyclopedia
Big-cone Pinyon is a 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:...

 in the pinyon pine
Pinyon pine
The pinyon pine group grows in the southwestern United States and in Mexico. The trees yield edible pinyon nuts, which were a staple of the Native Americans, and are still widely eaten...

 group, native to central 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...

. The range is highly localised, confined to a small area of the southern Sierra Madre Occidental
Sierra Madre Occidental
The Sierra Madre Occidental is a mountain range in western Mexico.-Setting:The range runs north to south, from just south of the Sonora–Arizona border southeast through eastern Sonora, western Chihuahua, Sinaloa, Durango, Zacatecas, Nayarit, Jalisco, Aguascalientes to Guanajuato, where it joins...

 in southern Zacatecas
Zacatecas
Zacatecas officially Estado Libre y Soberano de Zacatecas 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 Zacatecas....

. It occurs at moderate altitudes, from 1800-2400 m and 21° North latitude, in warm and temperate, dry climate conditions.

It is a small tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

, reaching 5-15 m tall and with a trunk diameter of up to 50 cm. The bark is brown, thick and fissured at the base of the trunk. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 ('needles') are in fascicles of five, slender, 7-13 cm long, and deep green to blue-green, with stomata confined to a bright white band on the inner surfaces. 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 ovoid, massive, 15-27 cm long and 8-14 broad and up to 2 kg 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 cones open to 10-15 cm broad when mature. The seeds are 2-3 cm long, with a thick shell, with a vestigial 1-2 mm wing; the seedlings have 18-24 cotyledon
Cotyledon
A cotyledon , is a significant part of the embryo within the seed of a plant. Upon germination, the cotyledon may become the embryonic first leaves of a seedling. The number of cotyledons present is one characteristic used by botanists to classify the flowering plants...

s, the highest number reported for any plant.

Because of its isolation in a remote area, it escaped discovery until 1964, when the Mexican botanist Jerzy Rzedowski
Jerzy Rzedowski
Jerzy Rzedowski Rotter is a Mexican botanist. He was born in Lwów, Poland .While he was young he was made prisoner by the Germans. He remained in a concentration camp until World War II finished and he was liberated by the Allies...

 noticed some unusually large pine nut
Pine nut
Pine nuts are the edible seeds of pines . About 20 species of pine produce seeds large enough to be worth harvesting; in other pines the seeds are also edible, but are too small to be of great value as a human food....

s (piñones) sold in the markets of local villages, and investigated the area to find their source. 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.

It has started being cultivated recently and is a very attractive tree as ornamental. The Mexican government has declared this species endangered.
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