The Nilgiri Biosphere Reserve includes all the important forest types that are to be found in South India as well as some that are just peculiar to the belt such as Tropical Thorn Forest, Tropical Dry Deciduous Forests, Tropical Moist Deciduous Forests, Tropical Semi Evergreen Forests, Sub Tropical Broad Leaved Forests, Tropical Wet Evergreen Forests, Southern Montane Wet Temperate Forests, Southern Montane Wet Grasslands and Subtropical Hill Savannas.
The NBR is spread over a large within three states and varied climatic zones. The forest divisions are as follows:
|Coimbatore Division||Nilgiri South Division||Erode Division|
|Satyamangalam Division||Nilambur Division||Mudumalai Sanctuary|
|Wyanad Division||Palghat Division||Chamrajnagar Division|
|Project Tiger Bandipur||Mysore Division||Hunsur Division|
The large contiguous extent of forest has the highest density of protected areas in the entire nation for so small an area.
|No.||Name||District||Area (ha)||Notification||Perceived Threats|
|1||Mudumalai WLS & NP||Nilgiris||21776||27.01.1940||Exotics, anthropogenic pressures|
|2||Mukurthi NP||Nilgiris||7846||15.10.1991||Introduction of exotics, poaching|
|3||Wyanad||Wyanad||34444||03.05.1973||Degradation, Biotic pressures|
|4||Bandipur NP||Mysore||87420||15.03.1985||Uncontrolled tourism|
|5||Nagarhole NP||Mysore & Kodagu||64339||01.04.1983||Uncontrolled tourism|
|6||Silent Valley NP||Palakkad||8952||15.11.1984||Extraction of medicinal plants, removal of timber & poaching|