Forest and Vegetation Types of Nepal

Nepal altitude varies from very lowland plain to the highest peak of the world so does the ecological zones varies and thus tree species varies according to the ecological zone above and below. Forest are classified based on ecological basis giving sufficient weigtage to both vegetation and climate. Forest restricted to particular area are omitted for generalization of forest type.

Nepal Forest

Types of Forest of Nepal

Forest are classified by different scholar. The most popular classification of forest by J.K. Jackson in 1994 is adopted here below. The types are:

1. Tropical Forest
2. Sub-tropical Forest
3. Temperate Forest
4. Sub-alpine Forest
5. Alpine Forest

Tropical Forest 

The tropical Forest lies below the altitude 1000 m above mean sea level. The types of Tropical Forest based on dominant tree species are: 

      a. Shorearobusta Forest: Greater part of this zone coverd by natural vegetation dominant by Shorea robusta, other associated species are Terminaliaalata, Adina cordifolia, Anogeissus latifolia, Syzyzium cumini Dillenla pentagyna, etc. The general appearance of Shorea robusta forest differes in hillside and plains. In plains they are generally larger and denser than in hills. Additional speicies are found in eastern Bhabar Terai Zone.

      b. Acacia catechu - Dalbergia sissoo Forest: Newly deposited alluvium, gravelly along streams and river. If alluvium not erroded eventually the forest succeeded to Shorea or other types of forest.

      c. Other riverain Forest: Small strips in moist loclities near streams, Syzyzium cumini dominant species in western  Nepal. This forest is not large and extends for from the streams.

      d. Grassland: Poorly drained clay place which was cleared once for cultivation covered with grass species of Saccharam spontaneum, Phragmiteskarka, Arundodonax, Eulaliopsisbinata, etc. The grasses may reached the height of 4 m. 

      e. Terminalia-Anogeissus deciduous hill forest: This forest in west upto 1200 m in foothills, where it replaces shorearobusta forest on south facing slopes. Terminalia alata and Anogeissus latifolia are dominant in dry south facing slopes. 

Sub-tropical Forest 

The sub-tropical forest lies between the altitude 1000 m and 1700 m East/2000 m West above mean sea level. The types of sub-tropical forest based on dominant tree species are:

      a. Pinus roxburghii Forest: It is found extensivelyat higher altitude in the west associated with Olea ferruginea, Pistacia species, etc. In the eastern part it is found in the large river valley. In transitional area mixed with Schimawallichii or Shorea robusta.

      b. Schima-castanopsis Forest
      c. Alnus nepalensis Forest
      d. Riverain Forest with Toona and  Albizia species

Temperate Forest 

The temperate forest lies between the altitude 1700 m to 2800 m in East and 2000 m to 31000 m in West above sea level. Temperate Forest broadly divided in two category. They are:

a. Lower Temperate Forest: The lower temperate forest lies between the altitude 1700 m to 2400 m in East and 2000 m to 2700 m in West above sea level. The types of Lower tropical forest based on dominant tree species are: 

        i.   Quercusleucotricophora and Quercuslanata Forest (Oak)

        ii.  Quercus floribunda Forest

        iii. Quercus lamellosa Forest

        iv.  Lower temperate mixed broad leaved forest with abundant lauraceae.

b. Upper Temperate Forest: The upper temperate forest lies between the altitude 2400 m to 2800 m in East and 2700 m to 3100 m in West above sea level. The types of Upper tropical forest based on dominant tree species are:

        i.   Quercussemecarpifolia Forest

        ii.  Upper temperate mixed broadleaved Forest

        iii. Rhododendron Forest

        iv.  Upper temperature coniferous Forest 

Sub-alpine Forest 

The sub-alpine forest lies between the altitude 2800 m to 3200 m in East and 3100 m to 4200 m in West above sea level. The types of Upper tropical forest based on dominant tree species are:

        i.   Abiesspectabilies Forest

        ii.  Betulautilis Forest

        iii. Rhododendron Forest

        iv.  Juniperusindica steppe

        v.   Caragana steppe

Alpine Forest

The apine forest lies at lower elevation below 4500 m from the mean sea level and it don't have any tree but have shrubby Rhododendrons and Junipers and some other shrubby species are found.