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Field experiments indicated that only 33% of larval and adult citrus thrips, Scirtothrips citri (Moulton), sampled on 2-m-high citrus trees originated from larvae that pupated in the ground. This estimate was reduced to 22% with 3-m-high trees that offered more pupation sites aboveground. Of the thrips that did drop to the ground for pupation, most did so in the NE quadrant, between 26 and 45 cm from the trunk.
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Grout et al. (1986) studied this question.
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