Included here are the western coastal plains (Malabar or Karala Coast) of Peninsula India from the southern vicinities of Broach to Cape Comorin, and the western side of the Western Ghats (Malabar Hills) including the Anamalai, Cardamom, Nilgiri and Palni hills. Several seasonal forests have been identified.
Malabar Semi-Evergreen Forests
West coast semi-evergreen forests are considered to be a transitional stage between evergreen and moist deciduous forests, and are sometimes associated with high levels of disturbances. They usually occur between altitudes of about 600 to 800 m and in some places extending up to 900 m. The main evergreen species include Artocarpus heterophyllus, Bischofia javanica, Calophyllum elatum, Euvodia lunuankenda, Mangifera indica, Mesua ferrea, Myristica dactyloides and the endemic Hopea ponga (Dipterocarpaceae) while the important deciduous elements are Acrocarpus fraxinifolius, Bombax ceiba, Chukrasia tabularis, Dalbergia latifolia, Grewia tiliaefolia, Terminalia bellirica, Toona ciliata and the endemic Lagerstroemia microcarpa (Lythraceae). Species composition at sub-canopy and ground level is similar to evergreen forests.
Malabar Dry Deciduous Forests
These forests are fairly rare in Kerala State and mainly confined to northern slope of Anamalai in Chinnar Wildlife Sanctuary, eastern part of Mannarkad Division, and the South Wayanad Wildlife Sanctuary where rainfall is less than 1200 mm. Their physiognomic structure is highly variable mainly due to impoverished soils, especially on steep slopes, but also due to anthropogenic instigated factors such as fire and grazing. Three types of are recognized. Forest dominated by Albizia amara, Gyrocarpus asiaticus and species of Acacia is found only in Chinnar Wildlife Sanctuary, up to an altitude of about 650 m. Other characteristic species include Erythroxylum monogynum, Dichrostachys cinerea, Chloroxylon swietenia and Hardwickia binata. On the lower slopes, species such as Acacia chundra and A. leucophloea are characteristic of scrub woodland and thickets, but where slopes with skeletal soils predominate tree savannas become an important feature. In such places Gyrocarpus asiaticus, with its metallic-coloured bark, becomes conspicuous together with other slope-loving species, such as Cochlospermum religiosum, Commiphora caudate, Givotia rottleriformis and Sterculia urens. Forest dominated by Anogeissus latifolia, Pterocarpus marsupium and species of Terminalia occurs above 600 m in Mannarkad Division and Chinnar Wildlife Sanctary. Again physiognomy varies ranging from savanna woodland to tree savanna. Other characteristic species include Dalbergia paniculata, D. latifolia, Emblica officinalis, Grewia tiliifolia and Kydia calycina. The third type of forest is dominated by Anogeissus latifolia, Tectona grandis and species of Terminalia. This is confined to the South Wayanad Wildlife Sanctuary where it ranges from dense forest to woodland savanna. Other common species include Careya arborea, Diospyros melanoxylon, Emblica officinalis, Lagerstroemia parviflora and Madhuca latifolia, but in low-lying areas where drainage is impeded Shorea roxburghii become conspicuous.
Malabar semi-evergreen Dipterocarpus indicus Forest
These forests vary in composition. In a wide area between Ariankavu Pass and the northern border of the Palaghat Gap dominant canopy species in addition to Dipterocarpus indicus include Strombosia ceylanica and to a lesser extent the gigantic Dipterocarpus bourdillonii. The latter generally occurs at lower limits (<450 m) and as a result of logging is now mainly encountered adjacent to streams and in some inaccessible areas. Other former climax species like Calophyllum polyanthum, Chrysophyllum roxburghii, Otonephelium stipulaceum, Poeciloneuron indicum, Semecarpus auriculata, Vateria indica and the endemic Palaquium ellipticum (Sapotaceae) have also become less frequent. On the other hand, certain widespread species such as Antiaris toxicaria, Artocarpus gomezianus, Bombax ceiba, Polyalthia fragrans and Pterygota alata and have become much more common and monopolize the canopy in places. These forests often surround small swamps especially in Ranni (between Plapally and Erumeli) and Kannur Divisions. Some of these are dominated by Humboldtia vahliana with its looping stilt roots while other species include Gymnacanthera canarica, Myristica dactyloides and the endemic Knema attenuata (Myristicaceae). To the south of the Ariankavu Pass, where the dry season varies from 2 to 3 months, canopy composition changes. Here Dipterocarpus indicus and Strombosia ceylanica are joined by Kingiodendron pinnatum as the main canopy species. However, in the humid valleys between Kallar and Shendurni rivers west of Agastya malai, Hopea racophloeaand and Humboldtia decurrens become common canopy species. The latter is a caulifliorus tree with large winged pinnate leaves and mainly prominent as a third story component. Other common canopy trees here include Artocarpus gomezianus, Ficus beddomei, Holigarna nigra, Otonephelium stipulaceum and Vateria Indica. Poeciloneuron indicum occurs in patches and Semecarpus auriculata and Semecarpus travancorica are common towards the lower limits. Common lower stratum species include Cynometra bedlomei, Fahrenheitia zeylanica, Hydnocarpus macrocarpa and the endemic Diospyros humilis and Diospyros paniculata (Ebenaceae).
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