The LSU (leaf sampling unit) structure has been set up: there are 130 LSUs at Sukamandang and 195 LSUs at Kumai. An initial leaf analysis carried out on samples taken in July 2004 revealed a generalized phosphorus deficiency, at both Kumai and Sukamandang. Nitrogen contents were satisfactory, whilst potassium contents were variable: higher on average at Sukamandang than at Kumai. A fertilizer schedule is proposed for 2005. It is recommended that a reference N-P-K-Mg mineral nutrition trial be set up at the beginning of 2005, along with an accompanying experiment to test the effect of boron on immature palms. It is essential to apply the entire recommended fertilization to rehabilitate the oil palm plantations within a reasonable time.