Pinus taiwanensis
Pinus taiwanensis
Pinus taiwanensis is an evergreen coniferous tree of the genus pine (Pinus ), usually with 10 to 20 centimeters long needles and 4-9 cm long seed cones. The distribution area is located on Taiwan and extends from 600 to 3400 meters altitude. There are two or three varieties. The wood has a good quality and has great economic importance to Taiwan. It is used under conditions other than lumber for the construction of wooden bridges and railway sleepers.
- 5.1 Literature
- 5.2 Notes and references
Description
Habit
Pinus taiwanensis is an evergreen, to 45 sometimes 50 meters high tree with a straight or more or less twisted trunk and a trunk diameter of up to 120 centimeters. The Stammborke is gray-brown to dark gray, rough and scaly and broken into large plates. The crown is broadly ovate and later like an umbrella. The first-order branches are long and are at level, shorten, however, with time, leaving only stumps remain. The branches of higher order are urged ascending and dense. Benadelte branches are bare, more or less smooth and light brown.
Buds and needles
The winter buds are reddish brown, ovoid - conical, 10 to 15 mm long, 5-7 mm wide and slightly resinous. The bud scales are pressed, orange, russet, white or colored fringed all white. The needles grow in pairs in a lasting, 10 to 15 millimeters long, thin basal needle sheath. The needles are straight or slightly curved, sometimes 5 usually 10 to 20 and rarely up to 22 centimeters long and 0.7 to 1 millimeter thick, with a semicircular cross section, thin, flexible, slightly twisted with finely serrated edges and a pointed tip. The needle can be formed from two to seven or eight central, or rarely near -surface resin canals. On all sides there are fine needle stomatal lines.
Cones and seeds
The pollen cones grow spirally arranged in groups. They are short cylindrical, 1.5 to 2 inches long with diameters 3-4 mm, yellow at first and later yellowish brown. The seed cones grow singly or sometimes in pairs on short stalks and remain on the tree for several years. They are light brown to dark chocolate brown, shiny, more or less asymmetrical, sometimes only 3 usually 4 to 9 and rarely up to 10 inches long, narrow ovate closed and open diameter of 2.5 to 5 centimeters. The seed scales are dull brown, thinly woody, rigid, elongated, straight, in the middle of the pin about 2 inches long and 1.3 inches wide. The apophysis is shiny brown, flat to slightly raised, with rhombic or rounded periphery, slightly wrinkled and transversely keeled. The umbo is broad ellipsoidal, reinforced flat and with a small, frail sting or unreinforced. The seeds are ellipsoid - ovoid, 5-6 mm long, flattened from 2.6 to 3.4 millimeters wide and easily without wings. The seed wing is 15 to 20 millimeters long, 5-6 mm wide and binding. Pollination is in April and May, the seeds mature in the second year in October.
Distribution, ecology and hazard
The natural range of Pinus taiwanensis is on Taiwan. Pinus taiwanensis grows in the mountains or along the mountainous coast. Inland, you can find them at altitudes 800-3000 m, exceptionally up to 3400 meters, where it remains dwarfed. Along the coast slopes it grows, down to 600 meters. Due to the large height differences in the distribution area it grows in several climates from warm temperate to subalpine climate. The distribution area is the Hardiness Zone 8 associated with mean annual minimum temperatures -12.1 to -6.7 ° C (10 ° to 20 ° F). In low and medium altitudes, it is on open areas exposed to the wind combing and restricted to sandy, acidic and nutrient-poor soils. They often grows together with representatives of different types of certificate chestnut ( Castanopsis ) and oaks (Quercus ).
The IUCN Red List is led Pinus taiwanensis as not at risk ( " Lower Risk / least concern "). It is noted, however, that a reassessment is pending.
Systematics and history of research
Pinus taiwanensis is a species in the genus of pine (Pinus ) in which it is assigned to the subgenus Pinus, section Pinus and Pinus subsection. She was described in 1911 by Hayata Bunzo first time scientifically. The genus name Pinus was already used by the Romans for several pine species. The specific epithet refers to taiwanensis the natural range of Taiwan.
Pinus taiwanensis is the Taiwanese representative of a group of three closely related and very similar species of Pinus luchuensis hwangshanensis on the continental China are counted in Japan and Pinus. These species are often either directly attributable to Pinus luchuensis or regarded as varieties or subspecies. Pinus luchuensis differs from Pinus taiwanensis by the longer needles, the lesser number of resin passages ( two to three instead of four to seven ), the shorter pin and the thinner cortex. Sometimes Pinus densiflora is attributed to this group. Pinus brevispica Hayata is another synonym of the type besides Pinus taiwanensis and Pinus luchuensis var luchuensis subsp. taiwanensis.
There are two varieties:
- Pinus taiwanensis var taiwanensis with rare 5 most from 10 to 15 and rarely up to 17 cm long needles and rarely from 3 usually 4 to 6 to 8 inches long and sometimes seed cones.
- Pinus taiwanensis var fragilissima ( Businsky ) Farjon with rare from 12 mostly 16 to 20 and rarely up to 22 cm long needles and sometimes from 5 usually 6-9, sometimes up to 10 cm long seed cones and often somewhat thinner seed scales. The distribution area of the variety lies in the district of Taidong and the Kuan Shan mountains. The taxon was founded in 2003 by Roman Businský as a separate species Pinus fragilissima ( basionym ) first described, Aljos Farjon ordered the taxon as a variety of the species Pinus taiwanensis to. He makes reference to the only small differences in the length of the needles and the seed cones and the presence of transitional forms, which is not justified a species status. Also, the thickness of the seed scales is clearly defined distinguishing feature no.
In the Flora of China is another variety, Pinus taiwanensis var damingshanensis the type attributed. Its distribution area is located in the Chinese provinces of Guangxi and Guizhou and is characterized by the center and near -surface resin canals. This property is, however, usually regarded as unreliable distinguishing feature. Mostly, all representatives from continental China are viewed as intrinsically Pinus hwangshanensis that of Pinus taiwanensis through the shorter needle sheaths (0.5 to 1 cm instead of 1 to 1.4 inches ), the denser teeth standing of the sawn needles ( in the mostly middle of the needle 43-57 teeth per centimeter instead of 26 to 35), the reddish-brown instead of yellowish- brown seed cones and the pressed- Umbo with lasting sting.
Use
The wood of Pinus taiwanensis has to use a good quality and adequate strength it as construction timber, for example, building and wooden bridges, as railway sleepers or props. It is also to fences and gates, packaging, panels used for making furniture, plywood, fiber board, and wood pulp.