Normally, rainforests rarely burn. In Amazonia, natural fires occur at an estimated rate of one fire every several hundred to several thousand years (Cochrane, et al., 1999). Primary forests are much more resistant to fire than are either secondary forest or selectively-logged forests. Human activities – leaving “slash” after logging and opening the forest by logging – reduce humidity, raise temperatures, and increase the probability of spontaneous fires. Such fires in themselves reduce the viability of the forest by removing most of the seeds and seedlings which could permit the area to reforest. A huge fire in Borneo in 1983 burned 3.5 million hectares of land after a drought, and similar extraordinary conflagrations occurred in Southeast Asia in 1997.