The above-ground part of fourteen, young (ten-year-old), rainfed olive trees were separated into trunk
(wood and bark), main branches (wood and bark), secondary branches (wood and bark), twigs, leaves
and fruits. Based on the dry matter and nutrient concentration in the different tissues, the total amounts
of nutrients in each tree were estimated. A controlled scheme of pruning conducted annually allowed the
quantification of the amount of nutrients removed in pruning. Olive yields and nutrient concentrations
in the fruits (pulp and pit) were used to quantify the nutrients removed in the crop. The results showed
that the amounts of nutrients annually removed were relatively low, suggesting that more conservative
fertilizer applications could be made than those usually recommended by the laboratories of soil testing
and plant analysis. In this orchard, with a yield goal of 2500 kg fruit ha−1, the nitrogen (N) rate to apply
as fertilizer should not exceed 20 kg N ha−1 year−1. The transient nature of N in the soil/plant systems
recommends that N be applied every year to increase the nutrient-use efficiency. The application of other
nutrients as fertilizer should be diagnosed beforehand by soil testing and/or plant analysis. Nutrients
removed by crop and pruning do not provide all the information on the need for supplemental fertilizer
applications. Soil testing and plant analysis should be used routinely for a continuous adjustment of the
fertilizer program.
