The chief feature of the moist deciduous forests is a leafless period in the dry season which may or may not begin with the cold weather. These forests have spread over an area of 60 sq.km. of the Sanctuary, over the ridges and lower slopes having elevation of 100m to 400m where the soil is generally rich. The top canopy remains leafless between March and May. Over most of the areas, teak plantations have been raised after Clear felling the indigenous species, growing in these forests, from 1913 to 1983. Naturally growing moist teak was one of the dominant species present in these forests. Kannimara teak tree having girth of 6.48 m and height 48.75 m is one the largest natural teak trees in Asia, which the tourists visit. In order to represent the old natural growth of Teak trees a plot has been preserved in Sungam range. It has been observed that the teak trees in the preserved plot have attained huge dimension and high floral diversity. In the past these forests have been exploited heavily. To start with, selected Teak and rose wood trees were felled and timber was extracted. No serious attempt was made to regenerate these species. Later on, when timber demand for these species increased, the forest areas were clear felled and mostly teak plantations were raised on these areas.

Physiognomically, the moist mixed deciduous forests have a closed canopy with tall and cylindrical trees. Trees tend to attain a height of 30.4 m and more. The under storey is well defined and the forest floor is full of vegetal growth. It has been observed in Anappady, Elathode and interstate boundary area that the floral elements of dry deciduous forests consisting of Anogeissus, Bombax, Tamarindus etc., exist within the Moist deciduous forests.

In Vengoli, Thellickal, Pulickal and Pooppara areas a good quality teak, rosewood, terminalias and Schleichera grows in depressions having rich soil. Bamboos also grow in abundance. In drier locality such as Anappady, Elathode, Thellickal east etc. Anogeissus, Albizzia, Sterculia, Grewia and Emblica trees are common. Bamboos are also found in dense thicket formations extensively. In areas such as Orukomban and Kothala, trees such as xylia xylocarpa and Grewia tilifolia come up in localized lateritic patches. The main species that are found in these forests are given below.

Canopy wise Species Distribution