Formation and characteristics of an Ultisol in Peninsular Malaysia utilized for oil palm production

Abstract. Most of the soils in the upland areas of Peninsular Malaysia are classified as Ultisols. Oil palm production on these soils is usually limited by their inherent low soil productivity. However, the crop is cultivated successfully on most of the soils following right soil management practices. A study was conducted in Bera, Malaysia to determine the characteristics and fertility of an Ultisol cropped to oil palm for many years continuously. In this study, the soil in the plantation was sampled, analyzed and classified. The soil under study was formed under tropical environment with udic moisture regime on fine-grained sedimentary rocks mixed with tuffs of Permian age. Due to very long exposure to the condition of high temperature and high rainfall throughout its development, the soil in the area was reddish in color, clayey, deep and highly weathered. The study found that the clay fraction of the soil was dominated by kaolinite, hematite, goethite and gibbsite; hence, the CEC and basic cations were low. Besides, soil reaction was acidic in nature with soil pH slightly below 5, but the exchangeable Al was more than 1 cmolc/kg soil. However, it was believed that these inherent characteristics were not expected to significantly affect the production of oil palm grown on the soil. With proper agronomic practices, the area can be utilized for oil palm production sustainably.