Early impact of oil palm planting density on vegetative and oil yield variables in West Africa

A range of various different planting distances (from 7.5 to 9.5 m) between oil palms were tested using an equilateral triangle design in a plantation density experiment which was settled in an oil palm commercial plantation in Nigeria. Climatic conditions were quite stable, with two seasons and around 2000 mm of annual rainfall. The soil was of desaturated ferralitic type, sandy on the surface, deep and without coarse elements. The early impact of plantation density was analysed at eight years after planting. Some early signs of depressive effect on yields were found for high planting densities (180 and 205 p/ha). Such a negative impact was not severe enough to counteract the effects of a higher number of palms per hectare. As a consequence, a gradient could be observed as yields (in tons of bunches per hectare) increased with density. We can anticipate that the competition effect between palms will increase over time with high densities, so that the counteracting point ought to be reached in a few years. A thinning treatment has been included in the protocol. Thinning was carried out at the end of the eight-year period.