Efficacy of foliar insecticides against spotted lanternfly infesting tree of heaven, 2023

The foliar application of 6 insecticides was evaluated for efficacy against spotted lanternfly (SLF) on tree of heaven. Potted tree of heaven plants in 6-gal containers in regular potting soil mix were used to cage 20 unsexed SLF adults. Plants were up to 3-ft tall and had at least 5 true leaves. SLF were collected from a tree line adjacent to a vineyard in Winchester, Virginia on the morning of 25 August 2023. The trial was set up in the afternoon of the same day in an open field at the Alson H. Smith Research and Extension Center in Winchester, Virginia. Cages containing 1 potted tree of heaven plant and 20 adult SLF were arranged in a 4 × 7 grid with 3-ft spacing between cages. Treatments, Imidacloprid + cyfluthrin (Temprid SC), beta-cyfluthrin + flupyradifurone (Temprid NG 30), deltamethrin (Suspend Polyzone SC), beta-cyfluthrin (Tempo SC Ultra), flupyradifurone (Altus SL), dinotefuran (Zylam L), and an untreated control check were assigned to cages in a RCB with 4 replicates. Each caged tree was considered as the experimental unit. All treatments were applied at 100 gpa and mixed with Nu Film P as an adjuvant at a rate of 8 fl oz per 100 gallons. Insecticides were applied as foliar sprays until run-off, using a CO₂ backpack with a TP Teejet 8003 VS nozzle at 30 psi. Potted trees were watered every other day, without removing the cages. The number of live SLF adults per cage was counted as 7 DAT. Treatment effects were evaluated by ANOVA using R studio (R Core Team 2023) and means were separated using Tukey’s HSD (α = 0.05). Data were transformed to meet normality assumptions using a square root transformation before analysis.

All tested insecticides were effective and all applications resulted in greater adult mortality on treated versus untreated plants (Table 1). Flupyradifurone (Altus SL) was the only insecticide that did not result in 100% mortality of adults during this trial (Table 1).¹

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