types of ever green trees

Semi-evergreen forests

Semi-evergreen forests (west coast semi-evergreen forests) are generally considered as a transitional stage between evergreen and moist deciduous forests. It is also found in localities where the evergreen forests are subjected to high disturbances. These forests occur between 600 to 800 m and in some places it extends up to 900 m. Animal species such as lion tailed macaque, Nilgiri langur, Nilgiri marten, small Travancore flying squirrel, brown mongoose, Malabar civet, and many birds such as the great Indian hornbill and the Bourdillon's great eared night jar occupy specific niches in these forests.

 

The floristic composition is an admixture of both evergreen and deciduous species in the top storey. The prominent evergreen species are Artocarpus heterophyllus, Bischofia javanica, Calophyllum elatum, Euvodia lunuankenda, Hopea ponga, Mangifera indica, Mesua ferrea and Myristica dactyloides. The deciduous floral elements include Acrocarpus fraxinifolius, Bombax ceiba, Chukrasia tabularis, Dalbergia latifolia, Grewia tiliaefolia, Lagerstroemia microcarpa, Pterospermum sp., Terminalia bellirica and Toona ciliata. The species occurring in the lower layer are the same as seen in the evergreen forests.

Southern Hill top Tropical Evergreen Forest

It is an inferior variety of the typical evergreen forest, reaching to a maximum height of only 10 m.

Distribution: This type of forest abounds in the Andamans and Western Ghats. They are usually seen on the slopes and tops of hills.

Locality factors: High winds, less favourable soil and climatic conditions restrict the formation of a climax. Rainfall is usually high, over 4500 mm and humidity is high even during periods of scanty rainfall.

Floristics: Top canopy trees & Second storey trees - Artocarpus heterophyllus, Canarium strictum, Cedrela toona, Cullenia exarillata, Dysoxylum malabaricum, Elaeocarpus seratus, Eugenia species, Holigarna beddomei, Mesua ferrea.

Bamboos :– Ochlandra travancorica

Shrubs: Pandanus spp, Strobilanthes spp
Climbers: – Calamus spp

West coast tropical evergreen Forest

These are dense evergreen forests with lofty trees of 45 m or more height. A large number of species occur mixed together. This makes the canopy extremely dense. Ferns, mosses, aroids and orchids are seen in plenty. The undergrowth consists of cane, creeping bamboo, and palms. With the increase in elevation and rainfall, the height of the forest diminishes, though it remains dense and evergreen, changing into the stunted wet sub-tropical forest.

Distribution: Enjoys a wide distribution over the Western Ghats
Locality Factors : It is seen in an altitudinal range of about 250-1200 m.The rainfall varies from 1500-5000mm.
Floristics: These forests are characteristic in having a high proportion of Mesua ferrea, Palaquium ellipticum, Cullenia exarillata and Calophyllum elatum. The absence of Hopea parviflora and Dipterocarpus indicus needs mention.
Top canopy trees: Artocarpus hirsutus, Bischofia javarnica, Canarium strictum, Calophyllum elatum, and Dysoxylum malabaricum
Second storey trees: Actinodaphne hookeri, Cinnamomum zeylanicum, Euphoria longana, Myristica beddomei, Vateria indica.
Shrubs: Leea indica, Pandanus spp, Strobilanthes spp, Rubiaceae
No grass in undistributed forest.
Climbers :– Climbers on the whole are not woody
Wet evergreen and semi-evergreen climax forests

In Kerala, wet evergreen forests are mostly confined to the windward side of the WG, where the rainfall is above 2000mm. By taking into account the distribution pattern of certain charactristic species, which reflect the climatic variations, the forests are further subdivided into eight main floristic types and three facies. All these types are classified according to low (0-800m), medium (800-1450m) and high (1400-1800m). The medium elevation forests in some places may appear at lower elevation (650 m ) due to local variations in the moisture and exposure.

Copyright © 2009 ---.