The World's Rubber Supplies

Abstract

Abstract Until the beginning of the present century, the world's supplies of crude rubber were obtained from trees and shrubs growing naturally in the equatorial regions of the earth, mainly in South and Central America and Central Africa; this rubber is generally known as wild rubber. Today, owing to the rapid increase in the production of cultivated rubber, the output of wild rubber is sufficient to supply only about 3 per cent of the world's requirements. In 1900 the total output of wild rubber amounted to about 54,000 tons, but this included considerable quantities of moisture and other impurities, and the dry rubber equivalent probably did not exceed 40,000 tons, while plantation output was nil. In 1929, the latest year for which complete statistics are available, the output of wild rubber was only 26,000 tons, while the output of cultivated rubber amounted to 821,000 tons. Cultivated or plantation rubber, as it is more generally called, is subdivided into estate and native rubber. Estate rubber is produced on estates owned and managed by Europeans, and on estates over 100 acres owned by Asiatics. Native rubber is produced on holdings under 100 acres. (Some of the larger native holdings in Sumatra and Dutch Bornea may be greater than 100 acres.)