Sathyamangalam is also the name of a Reserve Forest under the Wildlife Protection Act, 1973. It is contiguous with the Biligirirangan Temple Wildlife Sanctuary to the north in neighbouring Chamarajanagar District of Karnataka, and together forms a vital corridor for faunal movements, mainly elephants. The Sathyamangalam forest is tropical dry forest, part of the South Deccan Plateau dry deciduous forests ecoregion. It includes thorn forest, dry deciduous forest, and tropical hill forest.
Many of the higher elevations of the Bilgirirangan range have shola, or dwarf moist deciduous forest, and montane grassland habitats. These forests also harbour indigenous tribal people belonging largely to the Mullu Kurubas, Soliga communities. Southwards, the heights decrease into the arid Coimbatore plains before rising again into the Nilgiris and Anamalais.
A major National highway connecting Chamarajanagar to Coimbatore passes through the forests.
The forests are home to Asian Elephants, and the herd that ranges between the Western Ghats and Eastern Ghats through the Sathyamangalam forests numbers 6000 animals, the largest herd in India. Elephant movements in this corridor were the subject of one of the first studies on the Asian Elephant by the Indian elephant scientist R. Sukumar in early 1980's. The Sathyamangalam elephants were also the subject of Indian elephant expert Vivek Menon's book Tusker - The Story of the Asian Elephant.