2025/01/01 by Lucas E. Roscoe, Michael Stastny, Celia K. Boone +3 · 1 voice
Environmental Science · Agricultural and Biological Sciences · #Forest Insect Ecology and Management #Insect-Plant Interactions and Control #Plant and fungal interactions
paper · pdf · doi:10.4039/tce.2025.10018
openalex publication_date 2025/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/15
Abstract Adelges tsugae Annand (Hemiptera: Adelgidae), an invasive pest of eastern hemlock, Tsuga canadensis (Linnaeus) Carrière (Pinaceae), has been causing widespread tree decline and mortality across southwestern Nova Scotia, Canada, since its detection there in 2017. To gain basic knowledge of its biology in this novel part of its invaded range in eastern North America, we investigated the effect of predation on A. tsugae densities and conducted repeated surveys of the resident complex of natural enemies. We found only minimal and incidental predation by generalist arthropod predators, confirming the lack of population regulation by resident natural enemies, including predators of other adelgids. Our results suggest the role of escape from natural enemies in the pest’s rapid spread and impact in eastern Canada. In parallel, we tracked the timing of development through the complex life cycle of A. tsugae to compare its phenology to that in other invaded regions and to that of the closely related strain native to western North America. We discuss the implications of the local phenology of A. tsugae in the context of adopting a classical biological control programme, such as has been implemented in the United States of America, through the redistribution of native specialist predators of A. tsugae from British Columbia, Canada.