More than 90 percent of the Rubber produced in India is from Kerala. More than 80 percent of the area Under rubber in Kerala is accounted by small holdings. The present Rubber Board of India statistics are based mainly on the details available from the registered growers which contribute for only less than 50 percent of the production. Hence an attempt was made to map out the extent of area under rubber in Kerala using Remote Sensing Data.
Natural rubber can be extracted from the latex of over 895 species of plants, among which Have a brasiliensis is the most important commercial source of natural rubber. This is a quick growing and a tall plant which is a native of Brazil and was introduced to tropical Asia in 1876. Recently rubber is attaining more and more importance in the world market.As a result India, especially Kerala State, is showing an increasing trend in area under rubber during the recent years. According to Rubber Board of India (RBI) \, at present 88 percent of the total area under rubber belongs to Kerala State and 90 percent of India's production is also from this state.It is worth mentioning that ,in Kerala Rubber is grown in long areas probably due to high return ,attractive incentives offered by the Rubber Board of India and other socio economic reasons..As per Rubber Board of India estimate in Kerala nearly 20,000 hectares are being converted to rubber crop annually since 1980.
In Kerala rubber is generally grown in the midlands and high lands and a major portion of small holdings are in adjacent areas. The small holdings under rubber in Kerala are mainly homestead planting. This will include buildings, other crops etc. These homestead plantations are lying adjacent to each other. But they may not have uniformity in age and management. Mapping of major portion of these individual holding was possible from the aerial photographs. Mapping of these individual units was not possible with TM data due to the limitation of scale and resolution. Here the scale of TM used was 1:50,000 and so the smallest mappable unit was above5 hectares. Mapping of well maintained pure plantation was very easy from TM data. They showed bright reddish pink tone with smooth texture in the imagery. This is due to the uniformity in age, management etc. of the plants. Mapping of small holdings was not so easy compared to pure plantations. Due to the variation in age, management etc.