This research was carried out in a cultivated sago palm (Metroxylon sagu Rottb.) garden near Kendari, Southeast Sulawesi Province, Indonesia in 2006 to predict the annual starch yield from 2006 to 2015. The average trunk (with trunk height of >0.5 m) density and the average number of trunks in each class of length (at 1 m separation, from 1.0 to 10 m) per hectare were 228 palms/ha and 19 palms/ha, respectively. The trunk elongation rate was estimated to be 1m/year from the coefficient of regression line between the trunk length and the estimated years after trunk formation. The average number of harvestable trunks estimated by the elongation rate per year (1 m/year) and the trunk length at the harvesting stage (ca. 10 m) was 22 palms/ha/year, and the average annual starch yield per hectare was estimated to be 9.0 t from 2006 to 2015 with an average starch yield of 393 kg/palm by chemical analysis of mature palms grown around the surveyed area. However, the starch yield showed a downward trend from 13.5 t/ha in 2006 to 4.3 t/ha in 2015. This trend is caused by the decreasing numbers of harvestable trunks in each subsequent year. The above finding indicates that proper cultivation techniques to maintain a suitable trunk density with different trunk lengths (ages) by appropriate sucker thinning should be established for a stable annual starch production per unit area.

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