In general, tropical soils are not as agriculturally pro- ductive as temperate soils, and the soils of Southeast Asia are no exception to this statement. This is the case for two main reasons. First, the year-round high temperature and availability of water means that bacterial activity is high and thus organic material is rapidly broken down. The end result is that many tropical soils contain few or- ganic nutrients and that the organic material, if present at all, is found only in the top layer of soil. This is not a prob-