Pinus hartwegii

Hartwegii Pinus in the Sierra Madre

Pinus hartwegii is a native to Mexico and Guatemala kind of pines ( Pinus ). It is named after the German plant collector Karl Theodor Hartweg ( 1812-1871 ).

Features

Pinus hartwegii a tree stature heights of 20 to 30 meters and trunk diameter of up to 100 cm is reached. In old trees the lower branches the higher branches are large, thick and inclined downward, horizontal to slightly ascending. The branches form a thick, rounded crown. Young trees have a dense, pyramidal crown. The bark is reddish brown in old trees, thick and divided by narrow, vertical and horizontal cracks in large, flat, scaly plates. In young leaves, the bark is rough and furrowed but not divided into plates. The branches are thick, stiff, erect, rough and brown.

The needle leaves are in threes in bunches on short shoots, often to four and five. The sheaths are permanent brown and 10 to 15 mm long. They are thick, stiff, erect, 8-16 cm long and often stand in groups at the end of branches. The margin is finely serrated. There are three to twelve resin channels are present, often six or seven. There are two vascular bundles, which are very close together.

The cones are oblong - ovate, dark - purple. They are in groups of two to five in scaly, short stems.

The cones are long - ovate and almost symmetrical, slightly curved. They are 8-10 cm long, rarely up to 17 cm. You are at two to five very short stalks. The color is dark purple to black. The cones open to mature in winter and are semi - persistent. If they fall off the stalk and some of the lowest scales remain on the branch. The cone scales are thin, flexible. The apophysis is flat, transversely keeled, the umbo is located dorsally, is flat, very dark and armed with a small spine.

The seeds are about 5 mm long, almost black. The seed wing is 10 to 11 mm long, light brown. The number of cotyledons is usually five (rarely six).

The wood is hard, heavy, resinous. The sapwood is yellowish white, light brown and the heartwood. The wood is used for construction and lumber.

Occurrence

Pinus hartwegii is very scattered before in Mexico and Guatemala. In Mexico, the species in the states of Nuevo León, Tamaulipas, Hidalgo, Puebla, Veracruz, Tlaxcala, Mexico, Mexico City, Distrito Federal, Morelos, Colima, Michoacán, Jalisco, Oaxaca, and Chiapas is known. In Guatemala, it is found in the southern parts of the country. There are reports of occurrence in Honduras and El Salvador, whose membership is for style but questionable.

This species grows in high altitudes and often forms in 3000-3700 meters species pure stocks. In the snowy mountains of Mexico is the only pine species, which forms the tree line. In addition to snow and frost throughout the year, the wind is an important factor on these peaks.

Documents

Jesse P. Perry: The Pines of Mexico and Central America. Timber Press, Portland, 1991, pp. 126ff. ISBN 0-88192-174-2