| Summary: | <i>Scirtothrips dorsalis</i> Hood is an invasive and foliar pest of Florida blueberry that reduces plant growth by feeding on new leaf growth. A sampling plan is needed to make informed control decisions for <i>S. dorsalis</i> in blueberry. Fourteen blueberry fields in central Florida were surveyed in 2017 and 2018 after summer pruning to determine the spatial and temporal distribution of <i>S. dorsalis</i> and to develop a fixed-precision sampling plan. A sampling unit of ten blueberry shoots (with four to five leaves each) was collected from one blueberry bush at each point along a 40 × 40 m grid. Field counts of <i>S. dorsalis</i> varied largely ranging from zero to 1122 adults and larvae per sampling unit. <i>Scirtothrips dorsalis</i> had aggregated distribution that was consistent within fields and temporally stable between summers, according to Taylor’s power law (TPL) (aggregation parameter, <i>b</i> = 1.57), probability distributions (56 out of 70 sampling occasions fit the negative binomial distribution), Lloyd’s index (<i>b</i> > 1 in 94% occasions), and Spatial Analysis by Distance IndicEs (31% had significant clusters). The newly developed fixed-precision sampling plan required 167, 42, seven, or three sampling units to estimate a nominal mean density of 20 <i>S. dorsalis</i> per sampling unit with a precision of 5%, 10%, 25%, or 40%, respectively. New knowledge on <i>S. dorsalis</i> distribution will aid in evaluating the timing and effectiveness of control measures.
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