Oil palms with white stripe have greatly reduced yields. In the chlorotic areas of the leaflets, columnar palisade cells fail to develop and there is a reduction in air-space volume of the spongy mesophyll. Leaf area and photosynthetic activity are also reduced. Recovery of palms showing symptoms was spasmodic. The condition is discussed in relation to boron, to N/K ratio, polyphenols and availability of photosynthate.