Beef production systems in the tropics I. Extensive production systems on infertile soils

In contrast to raising beef cattle under conditions of improved grasslands with heavy carrying capacity, we will define “extensive production systems on infertile soils’ as the tropical savannas. This will include most of the extensively grazed lands in tropical Latin America which are utilized almost soley by cattle. The savannas occupy 18,130,000 km2. This is 13% of the world's total land area, compared with 8 to 9% for the humid tropical and 36% for the arid lands. Less than 1 % of the world's savannas are cultivated. Their population does not exceed 100 million, and the average density is no greater than seven persons per square kilometer (Grigg, 1970). Most of the tropical savannas are in Africa. Other large areas are in Australia and Latin America. Because of the author's personal experience, this paper will emphasize observations in Latin America. As indicated by Grigg (1970), the tropical savannas are characterized by a number of natural as well as socio-economic and agricultural features related to the land and its utilization which may help to explain why the tropics have half of the world's cattle, but produce only one-third of the world's meat and one-fifth of its milk