Within-Tree Distribution and a Fixed-Precision-Level Sampling Plan for the Orange striped Oakworm (Lepidoptera: Satumiidae)

Abstract

Within-tree distribution and dispersion of orange striped oakworm, Anisota Senatoria (J. E. Smith), was studied, and a sampling plan was developed. Significantly more A. senatoria eggs and early instars (first-second) were found in the low stratum of the canopy (1.7–3.6 m above ground) compared with middle (3.7–5.5 m) and high strata (5.6–7.6 m). Significantly more third instars were found in low and middle strata compared with the high stratum. Distribution of late instars (fourth-fifth) was not significantly different among strata. Dispersion indices demonstrated that Taylor’s power law provided a better fit to A. senatoria count data compared with Iwao’s patchiness regression. Taylor’s power law indicated that aggregation decreased from early to late instars. A fixed-precision-level sampling plan was developed that determined the minimum number of samples within a tree necessary to estimate the number of eggs and early ins tars present in the low stratum.