The Forest Survey of India (FSI) is the national organisation responsible for assessing, mapping and monitoring the forest resources of the country. Headquartered at Dehradun in Uttarakhand, it works under the Ministry of Environment, Forest and Climate Change and is best known for publishing the India State of Forest Report (ISFR), the official, regularly updated record of how much forest and tree cover India has and how it is changing.
Whenever a news report says that India’s forest cover has risen or fallen, the figure almost certainly comes from this institution. Understanding how the FSI collects its data, what it counts as “forest”, and why its definitions are sometimes debated, helps readers interpret those numbers sensibly. This explainer covers the history of the FSI, its functions, the methods behind the ISFR, the classes of forest cover, the national forest policy targets, and the continuing discussion about plantations and orchards.
Quick Facts
| Feature | Details |
|---|---|
| Full name | Forest Survey of India (FSI) |
| Established | 1 June 1981, as a successor to an earlier survey project of the 1960s |
| Headquarters | Dehradun, Uttarakhand |
| Parent ministry | Ministry of Environment, Forest and Climate Change |
| Flagship publication | India State of Forest Report (ISFR) |
| Frequency of report | Every two years (biennial), since 1987 |
| Method | Satellite remote sensing with field verification and forest inventory |
| Forest cover classes | Very Dense, Moderately Dense, Open Forest (plus Scrub) |
| Regional offices | Shimla, Kolkata, Nagpur and Bengaluru |
Origins and History of the FSI
The need for a reliable inventory of Indian forests was recognised soon after independence, since planners required accurate data for timber supply, industry and conservation. In the 1960s, a project known as the Preinvestment Survey of Forest Resources was started with international assistance to assess forests in selected regions. Its work showed the value of a permanent, professional agency, and the Government of India decided to establish a dedicated organisation.
The Forest Survey of India was formally set up on 1 June 1981, with its headquarters at Dehradun, a town that was already home to the Forest Research Institute and the Indian Forest Service college. It was assigned the task of carrying out regular surveys of the forest resources of the country, and it later took on a broader mandate covering monitoring, training and research.
Growth of its role
Over the decades, the FSI’s work expanded from basic timber-oriented inventories to a wide set of tasks related to environmental monitoring. Its first state of forest report appeared in 1987 and has been repeated every two years. In recent years it has also contributed data used for India’s national reporting on climate change and for international forest assessments.
Functions and Organisation
The FSI has a set of core functions that go beyond publishing a single report. Broadly, its responsibilities are as follows.
- Forest cover mapping: preparing periodic maps of forest cover and its changes using satellite data.
- Forest inventory: estimating growing stock, volume of wood, bamboo resources and carbon stock through field sampling.
- Trees outside forests: assessing trees on farms, roadsides, villages and urban areas.
- Forest fire monitoring: providing near real-time alerts of fire locations, which help state forest departments respond.
- Training and capacity building: training forest officials and other professionals in remote sensing, geographic information systems and inventory techniques.
- Consultancy and research: assisting states and agencies with project-specific surveys and technical studies.
Regional structure
Apart from its headquarters at Dehradun, the FSI has regional or zonal offices in Shimla, Kolkata, Nagpur and Bengaluru, which cover different parts of the country and coordinate with state forest departments. Field teams carry out ground verification, while the headquarters handles satellite data processing, analysis and publication.
The India State of Forest Report
The India State of Forest Report (ISFR) is the principal output of the FSI. It has been published every two years since 1987, with each edition numbered in sequence, and it presents the status of forest cover, tree cover, growing stock, carbon stock and other indicators at national, state and district levels. Each report compares the new data with those of the previous cycle so that changes can be tracked.
A typical report includes the following material.
- Total forest cover and its distribution across states and union territories.
- Forest cover divided into canopy density classes.
- Mangrove cover, tree cover outside forests and bamboo resources.
- Growing stock and forest carbon stock.
- Forest cover in tribal districts, in hill districts and in north-eastern states.
- Thematic chapters on forest fire, climate change and other emerging issues.
Why the report matters
The ISFR serves as an authoritative reference for governments, researchers and the public. State forest departments use it to plan afforestation and protection, and policy makers rely on it to track progress towards national goals, such as the target of increasing forest and tree cover. Journalists and activists also use its numbers to discuss deforestation and conservation. Because the report is regular and uses a consistent method, it is one of the longest-running official time series on forests anywhere in the developing world.
How Forest Cover Is Measured by Satellite
The FSI relies mainly on remote sensing, which means obtaining information about the land from satellites rather than by walking through every forest. India’s own Earth-observation satellites provide the images. Data from the Indian Remote Sensing programme, with a spatial resolution of a few tens of metres per pixel, are analysed to map where tree canopy exists.
From pixels to maps
The process involves several steps.
- Image acquisition: satellite images, typically taken in the dry season when tree canopies are most distinguishable, are collected for the entire country.
- Digital interpretation: software classifies each pixel according to its reflectance, which varies with vegetation density, and the result is refined with expert judgement and ancillary data.
- Ground truthing: field teams visit sample locations to check whether the map matches what is actually on the ground, and the classification is corrected when needed.
- Accuracy assessment: the final maps are tested statistically against independent field and high-resolution reference data.
Because the method detects canopy rather than the type of tree, satellite maps are good at measuring the extent and density of woody vegetation but cannot, by themselves, say whether a patch is a natural forest, a plantation or an orchard. This distinction is central to later sections of this article.
Definition and Classes of Forest Cover
For the purposes of the ISFR, “forest cover” means all land of more than one hectare in area with a tree canopy density of more than 10 per cent, irrespective of land ownership and legal status. This is a functional, canopy-based definition. It does not require the land to be legally notified as forest, and it can include private lands, plantations and orchards if they meet the size and canopy criteria.
The report divides forest cover into classes on the basis of canopy density, the proportion of the ground that is shaded by the crowns of trees when viewed from above.
| Class | Canopy density | Description |
|---|---|---|
| Very Dense Forest (VDF) | 70 per cent and above | The densest, closed canopy forests, usually found in well-protected, high-rainfall areas |
| Moderately Dense Forest (MDF) | 40 to 70 per cent | Substantial canopy but with some gaps; the largest class in most reports |
| Open Forest (OF) | 10 to 40 per cent | Sparse tree cover, including degraded forest and some plantations |
| Scrub | Below 10 per cent | Degraded forest land with scattered trees or bushes; not counted as forest cover |
Understanding the 70 per cent benchmark
The 70 per cent threshold for very dense forest is often misunderstood. It does not mean that 70 per cent of the area is forest; it refers to the density of the canopy within a forest patch. A very dense forest is one in which tree crowns shade at least 70 per cent of the ground, so little sunlight reaches the forest floor. Such forests are ecologically rich and relatively rare, and their loss is more serious than that of open forests since they take decades to regrow.
Recorded Forest Area, Forest Cover and Tree Cover
Three terms are frequently confused, and each has a different meaning.
- Recorded Forest Area (RFA): land that is legally notified or recorded as forest in government records. It is classified as Reserved Forest, Protected Forest or Unclassed Forest, according to the legal status. This area may or may not currently have tree canopy.
- Forest cover: land with the specified tree canopy, as seen by satellites, irrespective of legal status. Some forest cover lies outside the Recorded Forest Area, and some Recorded Forest Area has little or no cover.
- Tree cover: patches of trees smaller than one hectare, along with isolated trees, that occur outside the Recorded Forest Area. This includes trees on farmland, roadsides and in villages and towns.
Forest and tree cover combined
The National Forest Policy of 1988 set a long-term goal of having one-third of the country’s geographical area under forest or tree cover, with a higher proportion, about two-thirds, in hill and mountain regions. To measure progress against that goal, the ISFR adds forest cover and tree cover. In recent reports, the combined figure has been close to a quarter of India’s area, which means that the national target remains some way off.
Mangrove Cover Assessment
The FSI also reports on mangroves, the salt-tolerant forests that grow in coastal tidal areas. They are treated as a separate category because of their ecological importance and special habitat. Mangrove cover is mapped from satellite images in a similar way, with attention to tidal creeks, estuaries and deltas.
India’s mangroves are best known in the Sundarbans of West Bengal, the largest single mangrove region in the country, but they are also found in Odisha’s Bhitarkanika, the Andaman and Nicobar Islands, the coasts of Gujarat, Andhra Pradesh, Tamil Nadu, Maharashtra and other states. These forests play several valuable roles.
- They protect coastlines from storm surges, cyclones and erosion.
- They act as nurseries for fish and other marine life, supporting coastal fisheries.
- They store large amounts of carbon in their soils, which makes them important for climate mitigation.
- They provide habitat for species such as the Bengal tiger, saltwater crocodile and many bird species.
The ISFR reports mangrove cover by state and by canopy class and compares it with the previous assessment, which helps to monitor restoration programmes as well as losses to aquaculture, development and erosion.
Growing Stock, Carbon and Other Inventories
Besides mapping cover, the FSI carries out forest inventory work. Using a network of sample plots across the country, field teams measure tree species, girth, height and other parameters. The data are used to calculate the volume of wood in forests and in trees outside forests, which is known as the growing stock.
The same inventory feeds estimates of the carbon stored in India’s forests, in the above-ground biomass, below-ground roots, dead wood, litter and soil. These estimates are important for India’s reporting under international climate agreements, and for assessing the country’s goal of creating an additional carbon sink through forest and tree cover. The FSI also maintains assessments of bamboo resources, which are significant for rural livelihoods and handicrafts, and studies of non-timber forest produce.
The fire alert system
Another service of the FSI is a forest fire monitoring system. It uses satellite data to detect active fire points and sends alerts to forest officials, so that crews can respond quickly. Maps of fire-prone areas, drawn up using past fire records, help states plan prevention measures before the dry season.
The Debate: Do Plantations and Orchards Count as Forest?
The FSI’s definition of forest cover is based on canopy and size, not on species or legal status. This means that, when the satellite sees a large block of tree canopy of sufficient density, it is counted in the national figures. In practice, many kinds of tree-covered land may therefore be included, such as rubber and coconut plantations, orchards, tea estates with shade trees, bamboo groves and monoculture plantations of eucalyptus or teak.
Arguments raised by critics
Ecologists and environmental groups have long argued that a plantation is not equivalent to a natural forest. A natural forest has many species of plants, layers of vegetation and a complex food web, while a monoculture plantation or orchard has far fewer species. They contend that counting both as “forest” can give an inflated impression of ecological health and mask the loss of old-growth forests that are replaced by plantations.
The case made by the FSI and supporters
Supporters of the present approach point out that a uniform, objective, canopy-based definition allows consistent monitoring over time and across states, and that trees on any land contribute to carbon storage, soil protection and local livelihoods. They add that the report itself shows the density classes, which allows readers to look separately at the very dense category, and that it provides separate figures for plantations and trees outside forests in thematic sections. The FSI has also made efforts to refine its analysis over the years, for example by differentiating natural forests from plantations in some assessments.
The discussion has legal dimensions too. In its 1996 Godavarman judgment, the Supreme Court of India held that the word “forest” in forest laws should be understood according to its dictionary meaning, irrespective of ownership or classification, which broadened legal protection. The difference between this legal approach and the satellite-based cover approach is one reason why debates about forest data can be complex.
Challenges and the Road Ahead
The FSI faces a number of technical and policy challenges. Satellites with moderate resolution cannot easily detect small patches or distinguish tree species, so the organisation has been exploring finer-resolution data and better classification techniques, including those using machine learning. Cloud cover during the monsoon limits optical imagery in some regions, and rapid land-use change requires frequent updating.
There is also a continuing effort to improve the distinction between natural forest and other tree cover, to measure forest quality rather than only quantity, and to assess the health of ecosystems, such as biodiversity and regeneration. Greater transparency, public access to data and independent validation are often suggested as ways to strengthen confidence in the figures.
Conclusion
For more than four decades, the Forest Survey of India has provided the country with an indispensable record of its forests. Through its biennial reports, satellite maps, field inventories and fire alerts, it gives governments and citizens a common reference point for debates on conservation, climate and development. Its numbers should be read with an understanding of the definitions behind them: canopy-based forest cover is not the same as natural forest, and recorded forest area is not the same as green cover. When read carefully, the ISFR remains the best tool available to understand how India’s forests are changing and what remains to be done to reach the national goal.
Frequently Asked Questions
What is the Forest Survey of India?
The Forest Survey of India is a national organisation under the Ministry of Environment, Forest and Climate Change, headquartered at Dehradun. It was established in 1981 and is responsible for assessing and monitoring India’s forest and tree cover, mainly through satellite remote sensing and field inventories.
How often is the India State of Forest Report published?
The India State of Forest Report is published every two years. The first edition appeared in 1987, and each new report compares the latest data with the earlier cycle.
How is forest cover classified in India?
The FSI classifies forest cover by canopy density. Very Dense Forest has canopy density of 70 per cent and above, Moderately Dense Forest has 40 to 70 per cent, and Open Forest has 10 to 40 per cent. Areas with less than 10 per cent canopy are called scrub and are not counted as forest cover.
What is the difference between forest cover and recorded forest area?
Recorded forest area is land that is legally notified as forest in government records, whether or not it currently has trees. Forest cover is land with tree canopy, as seen from satellites, irrespective of its legal status. The two overlap but are not the same.
Do plantations and orchards count as forest in the ISFR?
Under the canopy-based definition, tree-covered land of more than one hectare with over 10 per cent canopy can be counted as forest cover, even when it is a plantation or orchard. Critics argue that this overstates natural forest, which is why the density classes and tree cover data are examined carefully.
What is India’s national target for forest and tree cover?
The National Forest Policy of 1988 set a goal of bringing one-third of the country’s geographical area under forest or tree cover, with about two-thirds in hill and mountain regions. Combined forest and tree cover is currently below that target, at roughly a quarter of the country’s area.
{“@context”:”https://schema.org”,”@graph”:[{“@type”:”FAQPage”,”mainEntity”:[{“@type”:”Question”,”name”:”What is the Forest Survey of India?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”The Forest Survey of India is a national organisation under the Ministry of Environment, Forest and Climate Change, headquartered at Dehradun. It was established in 1981 and is responsible for assessing and monitoring India’s forest and tree cover, mainly through satellite remote sensing and field inventories.”}},{“@type”:”Question”,”name”:”How often is the India State of Forest Report published?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”The India State of Forest Report is published every two years. The first edition appeared in 1987, and each new report compares the latest data with the earlier cycle.”}},{“@type”:”Question”,”name”:”How is forest cover classified in India?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”The FSI classifies forest cover by canopy density. Very Dense Forest has canopy density of 70 per cent and above, Moderately Dense Forest has 40 to 70 per cent, and Open Forest has 10 to 40 per cent. Areas with less than 10 per cent canopy are called scrub and are not counted as forest cover.”}},{“@type”:”Question”,”name”:”What is the difference between forest cover and recorded forest area?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”Recorded forest area is land that is legally notified as forest in government records, whether or not it currently has trees. Forest cover is land with tree canopy, as seen from satellites, irrespective of its legal status. The two overlap but are not the same.”}},{“@type”:”Question”,”name”:”Do plantations and orchards count as forest in the ISFR?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”Under the canopy-based definition, tree-covered land of more than one hectare with over 10 per cent canopy can be counted as forest cover, even when it is a plantation or orchard. Critics argue that this overstates natural forest, which is why the density classes and tree cover data are examined carefully.”}},{“@type”:”Question”,”name”:”What is India’s national target for forest and tree cover?”,”acceptedAnswer”:{“@type”:”Answer”,”text”:”The National Forest Policy of 1988 set a goal of bringing one-third of the country’s geographical area under forest or tree cover, with about two-thirds in hill and mountain regions. Combined forest and tree cover is currently below that target, at roughly a quarter of the country’s area.”}}]}]}
