A nondestructive sampling method was developed for Lycorma delicatula egg masses based on fixed-radius plot (100 m2) in 2020. All trees >1.0 cm DBH (diameter at breast height, 1.37 m in height) on each plot were visually inspected from the ground 4 m from the tree with binoculars. Egg masses found on trees were separated into six within-tree positions (lower trunk, middle trunk, upper trunk, first branch, second branch, above second branch) and recorded by cardinal directions, whereas those laid on shrubs/vines and stones were recorded without such separation. In total, 146 trees were inventoried at 28 plots over seven study sites (four plots per site). Egg masses were found on 19 tree species plus summer grape (Vitis aestivalis) and stone. Of the 421 total egg masses recorded, 31.1% were on Norway maple (Acer platanoides), followed by tree-of-heaven (Ailanthus altissima; 14.7%), black birch (Betula lenta; 12.6%), tuliptree (Liriodendron tulipifera; 11.9%), and American beech (Fagus grandifolia; 10.2%). Egg mass density per tree was positively correlated with tree diameter, and egg mass density per plot was positively correlated with plot basal area. Egg mass density after conversion ranged from 600 to 3,930 eggs masses/ha with no significant difference among study sites. Cardinal direction had no effect; however, significantly more egg masses were found on the first branches and upper trunks than other within-tree positions. Overall, branches were better than trunks in predicting egg mass number for the tree. The role of distance and late season adult aggregation on oviposition substrate selection are discussed.

The spatial distribution and seasonal dynamics of the spotted lanternfly (Lycorma delicatula) on tree of heaven (Ailanthus altissima) were studied in Pennsylvania through weekly sampling of 30 trees (6 sites, 5 trees/site) from 27 July to 8 November 2020. Adults found on each tree were separated into six within-tree positions (lower trunk, middle trunk, upper trunk, first branch, second branch, and above second branch) by four directions (East, South, West, and North). In total, 78,796 adults were counted at the six study sites during the 15-week period. Significant differences in total adult count were found among trees, with a mean of 2,627 (254–12,023) adults/tree. Study site, tree diameter, and cardinal direction had no significant impact on adult spatial distribution. However, significantly more adults were found on the middle (1077), the lower (865), and the upper trunk (337) compared with the first (194), the second (93), and above second branches (60). Most adults were congregated on the lower and middle trunks. Seasonal dynamics followed adult development and migration patterns in the field, with peak populations observed in weeks 35 (24–30 August) and 37 (7–13 September) before declining. Female-based sex ratios ranged from 77.3 to 100% according to weekly monitoring of the lower 1 m trunk of 10 trees at 2 sites (5 trees/site) for 12 weeks from 17 August to 8 November, with 7,356 females and 197 males counted, respectively. Impact factors such as attack patterns, intraspecific congregation, adult seasonality, and sexual dimorphism in host selection are discussed.

The northern walkingstick, Diapheromera femorata (Say), is the only stick insect of economic importance native to the United States. Young nymphs feed on various understory shrubs and trees whereas older nymphs and adults prefer oaks and cherries. Occasionally, field populations reach outbreak levels and cause complete tree defoliation. Widespread damage rarely occurs except those reported from Michigan

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