Distribution of 17-year periodical cicada (Hemiptera: Cicadidae) nymphal exuviae and oviposition injury in Mid-Atlantic apple orchards

Brood X of the 17-year periodical cicada (Hemiptera: Cicadidae), consisting predominantly of Magicicada septendecim (Linn.) and M. cassinii (Fisher), emerged in 2021. Mid-Atlantic tree fruit orchards are within the geographic range of this brood, and highly vulnerable to the effects of its oviposition in small branches. By weakening affected branches and causing branch breakage, oviposition injury from this species complex can significantly impact the structure of orchard trees and the capacity of injured branches to support fruit. Broad-spectrum insecticides, such as pyrethroids, are the only effective tools for managing this pest, and must be applied several times during the oviposition period for full protection, creating the potential for secondary pest outbreaks. Depending on the distribution of cicada injury within orchards, growers may need to treat only the most vulnerable portions or entire orchard blocks. We assessed the abundance of cicada exuviae in apple orchards that were established before 2004, the previous year of Brood X emergence, using linear transects of trees that extended from woods and non-woods borders into the orchard interior. We also quantified oviposition injury to small apple branches on trees in orchards established after 2004, using 50 flagged branches per row in the border row and rows extending into the orchard interior from woods and non-woods edges. Results are discussed in relation to the management of 17-year periodical cicada broods in tree fruit orchards.