''Trigonobalanus excelsa'' is a species of
plant in the family
Fagaceae
The Fagaceae are a family of flowering plants that includes beeches, chestnuts and oaks, and comprises eight genera with about 927 species. Fagaceae in temperate regions are mostly deciduous, whereas in the tropics, many species occur as evergre ...
. It is a tree
endemic to
Colombia
Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...
.
It is commonly known as black oak. The genus ''
Trigonobalanus'' is related to the true
oaks (''Quercus'') and includes three known species, ''T. excelsa'' and two species native to Southeast Asia.
[
]
Description
''Trigonobalanus excelsa'' is a tree which can grow to 20-40 meters tall.[
]
Range and habitat
''Trigonobalanus excelsa'' is known from five locations in the Colombian Andes. These locations are on different mountain ranges and distant from one another. The species' estimated area of occupancy
Area is the quantity that expresses the extent of a region on the plane or on a curved surface. The area of a plane region or ''plane area'' refers to the area of a shape or planar lamina, while '' surface area'' refers to the area of an open s ...
(AOO) is less than 500 km2.[
* The largest population is in Huila Department at the southern end of the Cordillera Oriental. It includes a black oak forest in Cueva de los Guácharos National Natural Park totaling 40,000 ha, and mountaintop black oak groves 50 km north in the towns of Pitalito, Suaza, Timaná, and Acevedo. Black oak is found only on the western slope of the cordillera.
* In Guantentá-Río Fonce Flora and Fauna Sanctuary near Santander in the Cordillera Oriental, in small patches in riparian corridors, among forests of white oak ('']Quercus humboldtii
''Quercus humboldtii'', commonly known as the Andean oak, Colombian oak or roble, is a species of oak found only in Colombia and Panamá. It is named for Alexander von Humboldt.
Description
''Quercus humboldtii'' is an evergreen tree which ...
'').
* In the municipalities of Amalfi, Antioquia and Serranía de San Lucas, Bolivar in the Cordillera Central Central Cordillera refers to the New Guinea Highlands.
Cordillera Central, meaning ''central range'' in Spanish, may refer to the following mountain ranges:
* Cordillera Central, Andes (disambiguation), several mountain ranges in South America
** ...
, 600 and 700 km north of the main Huila Department population.
* In Farallones de Cali National Natural Park and in Valle del Cauca in the Cordillera Occidental, about 200 km from the main Huila population.
It grows in humid Andean montane forests between 1,400- and 2,200-meters elevation. It is found in mixed forests and in monospecific stands, typically in areas with steep slopes and poor soils. Some populations grow near forests of white oak (''Quercus humboldtii'').[
]
Conservation
The species' conservation status is assessed as endangered. It is known from relatively small and isolated populations. Some populations are in protected areas. The main population in Huila is not protected and is threatened with habitat loss from ongoing deforestation. Other populations, like those in Antioquia and Bolivar departments, have been greatly reduced by deforestation, and survive only in remnant forest patches.[
]
References
{{Authority control
Fagaceae
Endemic flora of Colombia
Trees of South America
Vulnerable plants
Taxonomy articles created by Polbot
Flora of the northwestern Andean montane forests