Pinus hartwegii | |
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Hartweg's pines in Marquesa National Forest, between Mexico City and Toluca, Mexico, at about 3,500 m elevation | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Gymnospermae |
Division: | Pinophyta |
Class: | Pinopsida |
Order: | Pinales |
Family: | Pinaceae |
Genus: | Pinus |
Subgenus: | P. subg. Pinus |
Section: | P. sect. Trifoliae |
Subsection: | P. subsect. Ponderosae |
Species: | P. hartwegii |
Binomial name | |
Pinus hartwegii | |
Native range |
Pinus hartwegii (syn. P. rudis, P. donnell-smithii), Hartweg's pine, the Mexican mountain pine, or pino de las alturas, is a pine native to the mountains of Mexico and Central America east to Honduras. It is named after Karl Theodor Hartweg, who described it in 1838.
Pinus hartwegii is a very high elevation species, growing at elevations of 2,500–4,300 metres (8,200–14,100 ft). It forms the alpine tree line on most of Mexico's higher mountains. It grows on both the Sierra Madre Occidental and Sierra Madre Oriental (mountain ranges) (29° North latitude) from Chihuahua State and Nuevo León (26°) to the highest peaks in the mountain ranges on the El Salvador—Honduras border (15° North latitude). In the Sierra Madre Occidental this pine grows with very dry winters and a very heavy rainy season in summer, with constant frosts from October to March.
This pine does not acquire the dwarfed and contorted shape shared by many species at high elevation. Even at the alpine tree line, this tree is not damaged by the cold and wind-blown ice present at that elevation. Consequently, Pinus hartwegii has been studied as an evolutionarily unique member on tree line ecophysiology.
Pinus hartwegii is an evergreen tree reaching 20–30 metres (66–98 ft) in height, with a broad, rounded crown. The bark is thick, dark grey-brown, and scaly or fissured. The leaves are needle-like, dark green, five (occasionally four) per fascicle, 10–20 cm long and 1.2-1.5 mm thick, the persistent fascicle sheath 1.5–2 cm long.
The cones are ovoid, 6–13 cm long, black or very dark purple, opening when mature in spring to 5–7 cm broad. The seeds are winged, 5–6 mm long with a 1.5-2.5 cm wing. Pollination is in late spring, with the cones maturing 20–22 months after.
It is closely related to Pinus montezumae (Montezuma pine), differing from it in the shorter leaves, black (not brown) and smaller cones; it replaces Montezuma pine at high elevations, and often hybridises with it where they meet at middle elevations.
Pinus flexilis, the limber pine, is a species of pine tree in the family Pinaceae that occurs in the mountains of the Western United States, Mexico, and Canada. It is also called Rocky Mountain white pine.
Pinus strobiformis, commonly known as southwestern white pine, Mexican white pine or Chihuahua white pine, is a medium-sized white pine tree whose native habitat is in southwestern United States and Mexico. It is typically a high-elevation pine growing mixed with other conifers.
Pinus arizonica, commonly known as the Arizona pine, is a medium-sized pine in northern Mexico, southeast Arizona, southwest New Mexico, and western Texas in the United States. It is a tree growing to 25–35 m tall, with a trunk diameter of up to 1.2 m. The needles are in bundles of 3, 4, or 5, with 5-needle fascicles being the most prevalent. This variability may be a sign of hybridization with the closely related ponderosa pine. The cones are single, paired, or in whorls of three, and 5–11 cm long.
Pinus engelmannii, commonly known as the Apache pine, is a tree of Northern Mexico, in the Sierra Madre Occidental with its range extending into the Southwestern United States. This pine is a medium-sized species with a height of 20–30 metres and a trunk diameter of 35–80 centimetres.
Pinus leiophylla, commonly known as Chihuahua pine, smooth-leaf pine, and yellow pine, is a tree with a range primarily in Mexico, with a small extension into the United States in southeast Arizona and southwest New Mexico. The Mexican range extends along the Sierra Madre Occidental and Sierra Madre del Sur 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.
Pinus cembroides, also known as pinyon pine, Mexican pinyon, Mexican nut pine, and Mexican stone pine, is a pine in the pinyon pine group, native to western North America. It grows in areas with low levels of rainfall and its range extends southwards from Arizona, Texas and New Mexico in the United States into Mexico. It typically grows at altitudes between 1,600 and 2,400 metres. It is a small pine growing to about 20 m (66 ft) with a trunk diameter of up to 50 cm (20 in). The seeds are large and form part of the diet of the Mexican jay and Abert's squirrel. They are also collected for human consumption, being the most widely used pine nut in Mexico. This is a common pine with a wide range and the International Union for Conservation of Nature has rated its conservation status as being of "least concern".
Pinus johannis, the Johann's pine, is a pine in the pinyon pine group, native to North America. The range extends from southeast Arizona and southwest New Mexico, United States, south in Mexico along the Sierra Madre Occidental and the Sierra Madre Oriental to southern Zacatecas and San Luis Potosí. It occurs at moderate to high altitudes, from 1,600–3,000 metres (5,200–9,800 ft), in cool, dry climate conditions.
Pinus culminicola, commonly known as Potosí pinyon or Potosí Piñón, is a pine in the pinyon pine group, native and endemic to northeast Mexico. The range is highly localised, confined to a small area of high summits in the northern Sierra Madre Oriental in Coahuila and Nuevo León, and only abundant on the highest peak, Cerro Potosí. It occurs at very high altitudes, from 3000–3700 m, in cool, moist subalpine climate conditions.
Pinus edulis, the Colorado pinyon, two-needle piñon, pinyon pine, or simply piñon, is a pine in the pinyon pine group native to the Southwestern United States, used for its edible pine nuts.
Pinus ayacahuite, also called ayacahuite pine and Mexican white pine, is a species of pine native to the mountains of southern Mexico and western Central America, in the Sierra Madre del Sur mountains and the eastern end of the Eje Volcánico Transversal, between 14° and 21°N latitude in the Mexican states of Guerrero, Oaxaca, Puebla, Veracruz and Chiapas, and in Guatemala, El Salvador and Honduras. It grows on relatively moist areas with summer rainfalls, however specimens from its eastern and southern distribution live under really wet conditions; it needs full sun and well drained soils. Its temperature needs fluctuate between 19 and 10 °C on average a year. This tree accepts from subtropical to cool climate.
Pinus aristata, the Rocky Mountain bristlecone pine or Colorado bristlecone pine is a long-lived species of bristlecone pine tree native to the United States. It is found in the Rocky Mountains in Colorado and northern New Mexico, with an isolated population in the San Francisco Peaks of Arizona. It is found at very high altitudes, from 2,100 to 4,000 meters in cold, dry subalpine climate conditions, often at the tree line, although it also forms extensive closed-canopy stands at somewhat lower elevations.
Picea engelmannii, with the common names Engelmann spruce, white spruce, mountain spruce, and silver spruce, is a species of spruce native to western North America. It is mostly a high-elevation mountain tree but also appears in watered canyons.
The Sierra Madre Occidental pine–oak forests are a Temperate broadleaf and mixed forests ecoregion of the Sierra Madre Occidental range from the southwest USA region to the western part of Mexico. They are home to a large number of endemic plants and important habitat for wildlife.
Pinus hwangshanensis, or Huangshan pine, is a species of pine endemic to the mountains of eastern China; it is named after the Huangshan Mountains in Anhui, from where it was first described.
Pinus durangensis, the Durango pine, is a pine tree species endemic to the Sierra Madre Occidental mountain range of north-western Mexico.
Pinus maximartinezii, called Martinez pinyon, big-cone pinyon or maxipiñon, is a pine in the pinyon pine group, native to west-central Mexico.
Pinus douglasiana is a species of evergreen conifer in the family Pinaceae. It is found only in Mexico.
Pinus montezumae, known as the Montezuma pine, is a species of conifer in the family Pinaceae.
The Trans-Mexican Volcanic Belt pine–oak forests is a subtropical coniferous forest ecoregion of the Trans-Mexican Volcanic Belt of central Mexico.
The Zacatonal is a montane grassland and shrubland ecoregion of central Mexico.