PASTURE RENOVATION PRACTICES OF FARMERS IN THE NEOTROPICAL SAVANNAS

Degradation of sown pastures in the neotropics is a well known but poo rly documented phenomenon. The paper reports the results of a survey c onducted in the eastern savannahs of Colombia to quantify farmers' rea ctions to perceived pasture degradation. The survey was conducted in a n area of 23 644 km(2). The sample consisted of 46 farms, which had 19 012 ha of Brachiaria decumbens pastures distributed in 374 paddocks. O f these paddocks, 196 had been sown with vegetative seed, and 281 had received modest rates of P fertilization at planting. Pastures sown on flat lands had younger modal ages (three years) and were renovated mo re frequently than those sown on hilly or dissected savannahs (10 year s). These differences were probably a result of variations in infrastr ucture and relative stage of development of the two topographies, but slight differences in inherent soil fertility may also have played a r ole. We found no relationship between grazing management and frequency of pasture renovation. Implications for future research on pasture re clamation are discussed. (C) 1998 John Wiley & Sons, Ltd.