Pinus pungens
| Pinus pungens | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Pinus pungens on Blue Ridge Parkway , Virginia |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Pinus pungens | ||||||||||||
| Lamb. |
Pinus pungens is an evergreen conifer from the genus of the pines ( Pinus ) with usually 5 to 7 centimeters long, in groups of two or less often three growing needles and 5 to 10 centimeters long seed cones. The natural range is in the Appalachian Mountains in the southeastern United States. It is classified as not endangered inthe IUCN Red List . The species is of little economic importance and is used as firewood and for the production of cellulose .
description
Appearance
Pinus pungens grows as an evergreen tree , usually 12 to 15 meters high. The trunk is straight or crooked and reaches a diameter of 60 centimeters at chest height . The largest known tree, which was measured in 1984, reached a height of 28.7 meters, a trunk diameter of 80 centimeters and a crown diameter of 14 meters. The trunk bark is thin, rough and scaly and breaks into reddish-brown to gray-brown, irregular plates, which are separated by shallow dark furrows. The few main branches are horizontal and form a broad, flat crown. The needled branches are horizontal or erect, they are thin, rough due to pulvini , hairless, initially yellowish green and later yellowish brown to dark reddish brown.
Buds and needles
The buds are red-brown, egg-shaped to short cylindrical, 6 to 9 millimeters long and resinous. The needles usually grow in pairs, rarely in threes, in a permanent, basal needle sheath that is initially 5 to 10 millimeters long and later shortens to 4 to 6 millimeters. The needles are green, straight or more or less curved, stiff, often twisted, usually 5 to 7 centimeters, rarely from 3 to 8 centimeters long and 1 to 1.5 millimeters thick. You stay on the tree for three years. The edge of the needle is finely sawn, the end pointed to short and pointed and piercing. There are fine stomata lines on all needle sides . Usually two to seven, rarely fewer or up to 11 resin canals are formed.
Cones and seeds
The pollen cones grow spirally arranged in dense groups. They are bright red at first and later when the pollen ripens and the pollen sacs swell yellow and about 1.5 centimeters long. The seed cones rarely grow individually, mostly in whorls of three to six or more on the sides of the branches. They are almost sessile to short stalked, asymmetrically ovoid-conical, 5 to 10 centimeters long with a diameter of 4 to 6 centimeters. The cones open in the course of two to three, rarely five years, and then stay on the tree for up to 30 years before they fall off together with the stem. The open cones reach their largest diameter of 8 centimeters at the base. The 90 to 140 seed scales are thickly woody and wedge-shaped. The apophysis is clearly raised, transversely keeled, diamond-shaped in outline in the center of the cone, conical and bent back at the cone base, orange-brown or yellowish brown. The umbo is strong and armed with a dark, sharp thorn . The seeds are obovate, somewhat angular and flattened, 5 to 6 millimeters long and black-brown. The seed wings are 15 to 25, rarely 30 millimeters long, and brown.
Chromosome number
The number of chromosomes is 2n = 24.
Pinus pungens in North Carolina
Branch and cones
Twigs and needles
Young seed cone
Distribution, ecology and endangerment
The natural range of Pinus pungens is in the Appalachian Mountains in the states of New Jersey , Pennsylvania , West Virginia , Delaware , northern Georgia , Maryland , western North Carolina , South Carolina , Tennessee and Virginia .
The species grows on dry, stony slopes in the Appalachian Mountains from the foothills to the summit region at heights of 350 to 1100 meters, rarely from 100 to 1400 meters. This makes it the highest mountain pine species in the southeastern United States. In the south of the distribution area it is the dominant tree species over 1300 meters. It grows on different soils, but avoids calcareous subsoil. In areas mainly determined by deciduous forest, the distribution area is limited to rocky subsoil. The mean annual precipitation varies from north to south and depending on the altitude between 760 and 2100 millimeters. The summers are cool to warm, the winters moderately cold and humid. The distribution area is assigned to winter hardiness zone 6 with mean annual minimum temperatures between −23.3 ° and −17.8 ° Celsius (−10 to 0 ° Fahrenheit ).
Pinus pungens is a pioneer species that can spread quickly after parts of the forest have been destroyed, for example by fire, or it can also repopulate abandoned fields. Although adult trees are killed by fire because of their comparatively thin bark, like most southern pines in the United States, reproduction depends on fire. The thick seed cones survive the forest fires and enable the stands to be regenerated due to the late release of the seeds. In fact, the death of the mature trees even favors the growth of the seedlings .
In well-established stands it is found together with Pinus rigida and at lower altitudes with Pinus virginiana or with deciduous tree species such as the red maple ( Acer rubrum ), the black tupelo tree ( Nyssa sylvatica ), the basket oak ( Quercus michauxii ), the scarlet - Oak ( Quercus coccinea ), the dyer's oak ( Quercus velutina ), the American chestnut ( Castanea dentata ) or the sour tree ( Oxydendrum arboreum ). Different types of rhododendrons ( Rhododendron ), blueberries ( Vaccinium ) and humpbackberries ( Gaylussacia ) together with the broad-leaved bay rose ( Kalmia latifolia ), the mountain holly ( Ilex montana ) and the windlass ( Smilax glauca ) are particularly common on steep mountain slopes dense undergrowth .
In the Red List of the IUCN is table mountain pine classified as endangered ( "Lower Risk / least concern"). However, it should be noted that a reassessment is necessary.
Systematics
Pinus pungens is a species from the genus of the pines ( Pinus ), in which it is assigned to the subgenus Pinus , Section Trifoliae and Subsection Australes . It was first scientifically described in 1805 by Aylmer Bourke Lambert in the Annals of Botany . The generic name Pinus was already used by the Romans for several types of pine. The specific epithet pungens comes from Latin and means "stinging" and thus refers to the sharp sting of the umbo. There are no known synonyms of the species.
Pinus pungens forms natural hybrids with Pinus rigida and artificial hybrids with Pinus echinata .
use
Due to their small size and often crooked growth, Pinus pungens is of little value as a supplier of wood. The wood is used as firewood or processed into pulp . However, it has a certain ecological importance due to the consolidation of unstable mountain slopes and as a habitat for many wild animals. The species is rarely used in gardens and is restricted to botanical gardens and arboretums in North America and Europe.
swell
literature
- Aljos Farjon: A Handbook of the World's Conifers . tape 2 . Brill, Leiden-Boston 2010, ISBN 90-04-17718-3 , pp. 746-747 .
- James E. Eckenwalder: Conifers of the World. The Complete Reference . Timber Press, Portland, OR / London 2009, ISBN 978-0-88192-974-4 , pp. 468-469 .
- Flora of North America Editorial Committee (Ed.): Flora of North America North of Mexico . Volume 2: Pteridophytes and Gymnosperms . Oxford University Press, New York / Oxford a. a. 1993, ISBN 0-19-508242-7 (English).
- Helmut Genaust: Etymological dictionary of botanical plant names. 3rd, completely revised and expanded edition. Nikol, Hamburg 2005, ISBN 3-937872-16-7 , pp. 487, 519 (reprint from 1996).
Individual evidence
- ↑ a b c d e Aljos Farjon: A Handbook of the World's Conifers , Volume 2, p. 746
- ↑ a b c d e f James E. Eckenwalder: Conifers of the World , p. 473
- ^ Robert Kral: Pinus pungens in Flora of North America , Volume 2
- ↑ a b Pinus pungens in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved May 20, 2013.
- ^ Aljos Farjon: A Handbook of the World's Conifers , Volume 2, pp. 746-747
- ^ A b Aljos Farjon: A Handbook of the World's Conifers , Volume 2, p. 747
- ↑ Pinus pungens in the endangered Red List species the IUCN 2012. Posted by: Conifer Specialist Group, 1998. Accessed May 22, 2013.
- ↑ a b Pinus pungens. In: The Plant List. Retrieved May 22, 2013 .
- ↑ Exactly: Etymological dictionary of botanical plant names p. 487
- ↑ Exactly: Etymological dictionary of botanical plant names p. 519
Web links
- Christopher J. Earle: Pinus pungens. In: The Gymnosperm Database. www.conifers.org, November 23, 2012, accessed on May 22, 2013 (English).
- Pinus pungens at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed May 22, 2013.