Within-tree distribution of an insect pest is useful to determine sample unit, sampling location, and required sample number for this pest within a tree. This study was conducted to characterize the within-tree distribution pattern and determine an efficient sample unit for eggs of Ricania shantungensis (Hemiptera: Ricaniidae) on a chestnut tree. A total of 60 chestnut trees were randomly selected from chestnut fields in Gongju-Si and Buyeo-Gun, Korea in 2019. For each tree, 12 branches were cut at three vertical heights (low, middle, and high) in four cardinal directions (east, west, south, and north). The cut branches were observed for counting the number of egg masses per 10 cm from the branch tip. Coefficient of variation (CV) and coefficient of determination (r²) were calculated and used to determine an optimal sample unit for eggs of R. shantungensis on chestnut trees. Numbers of R. shantungensis egg masses were not significantly different (P > 0.05) vertically and horizontally within a tree. Based on CV and r² values, the 50 cm branch tip would be the optimal sample unit for R. shantungensis eggs. Using this small sample unit for sampling of R. shantungensis eggs could be economical and efficient.

害虫在树内的分布对于确定树中该害虫的采样单位，采样位置和所需的样本数量很有用。进行这项研究来表征树内分布模式，并确定板栗树上Ricania shantungensis（Hemiptera：Ricaniidae）卵的有效样本单位。2019年，从韩国公主州和扶余郡的栗田中随机选择了60棵栗树。每棵树在四个基本方向上以三个垂直高度（低，中和高）切开12根树枝（东，西，南和北）。观察切下的分支以计数离分支尖端每10cm的卵团数。变化系数（CV）和确定系数（r ²）被计算并用于确定板栗树上山东桐的卵的最佳样品单位。 在一棵树内，山东通体卵的数量在垂直和水平上没有显着差异（P > 0.05）。根据CV和r ²值，50 cm的分支尖端将是山东通花卵的最佳样品单位。使用这种小样本单位对山东桐花卵进行采样可能是经济有效的。