Sathyamangalam division is located in the Erode district of Tamil Nadu and lies within the boundary of the Nilgiri Biosphere Reserve. It is located within 11°29′ 11°48′ N and 76°50′ 77°27′ E. The region has an area of 1455.3 sq km and receives as much as 850 mm of rains per year. The forested areas start from the Moyar Valley up to the Dhimbam hills. The forest division under Sathyamangalam is widely regarded as one of the richest forest regions of the state of Tamil Nadu. The Sathy forests as Sathyamangalam is commonly called are contiguous with the forests of Nilgiri District, the Biligirirangan Sanctuary as well as forests of Kollegal and Chamrajnagar in Karnataka, thus forming a large patch of forests representing the eastern ghat ecotype. The elevation ranges from 280 1698 msl.
Southern thorn forest: This forest type is prevalent in plains and foothills and also in the western fringes of the Talamalai plateau receiving poor rainfall (600 800 mm). Soil is shallow thin and stony. Out crop of gneiss and granite rocks are met with frequently. Trees are stunted, short boled and with low branching crowns. Lower storey is not well defined and comprises of xerophytic shrub growth. Sandal is present in very small quantity and rarely forms heartwood. Degradation Stages: A. Southern thorn scrubs: B. Southern Euphorbia scrub
Southern dry mixed deciduous forests: This is the most common forest climax type met within this Division and also economically very valuable owing to the presence of sandal and bamboo. This type of forest occurs almost in the entire plateau, with slight variations in the component species according to edaphic and climatic conditions. The terrain is flat, and undulating and at elevation between 700 1200 m. The rainfall varies from 800 1500 mm. It merges with thorn forests wherever the rainfall drops below 800-875 mm. Presence of Bamboos and sandal is largely confined to this type of forests. Degradation stages: a) Dry deciduous scrubs, b) Dry savannah Forest, c) Euphorbia scrub type.
Sandal Occurrence: Sandal is a species of deciduous associate formations and it is a transitory species occurring in preclimax vegetation. Conditions conducive for its growth and dissemination are found in Talamalai, Hasanur Valley, Yekkathur and Gundri plateau and Talamalai plateau. It grows in patches of varying density and size and is found growing in almost every type of soil – on stony red soil around Yekkathur, on rich loam near Geddasal, on slopes of black clayey soil near Hassanur and in arid soils in Talamalai reserve. Sandal is completely absent in moist and fertile localities such as Minchikuli valley.
Southern tropical semi evergreen forests: This forest type occurs in a transition zone at elevation above 1200 m between the dry deciduous forests and sub tropical hill forest or as an edaphic sub climax in a few favorable pockets. This type is met within Minchikuli valley. As this type is an intermediary between tropical evergreen and moist deciduous forest, the dominants of both and usually found mixed. Soil is generally an argillaceous loam with plenty of humus. The vegetation is dense and tends to be semi evergreen.
Southern sub tropical hill forests: This forest type is confined to hilltops generally above an altitude of 1600 M with rainfall of well over 2000 mm. This is commonly referred to as the hill shola forest and is very characteristic in its shapely appearance – small extents of rounded sholas surrounded by rolling grasslands. The branches of the trees are heavily laden with moss, which provided an ideal substratum for the growth of epiphytes orchids and ferns. These forests are of importance as gene pool reserves.
Dry tropical riverine forests: Along the watercourses, streams and riverbanks a well marked narrow fringe of large trees are present. The trees are widely spaced with smaller trees and shrubs between and often coarse grass.