Entomological investigations in a novel agroforestry crop to the Midwestern US: Arthropod pests, their damage, distributions, and resistance factors associated with hybrid hazelnuts (Corylus americana x Corylus avellana)

Abstract

Hazelnuts (Corylus spp.) (Fagales: Betulaceae) are an emerging crop within the upper Midwest. New interspecific hybrid crosses between European (Corylus avellana) and American (Corylus americana) hazel species are being utilized as crops within sustainable agroecosystems. As perennial shrubs, hazels hold soil, cycle nutrients, while requiring only minimal inputs. As these plantings have developed, however, growers and researchers have noticed several insects and mites feeding on and causing damage to the plants. Over the past decade, several arthropod pests, comprising both introduced and native species, have been identified as potentially serious limitations to hazelnut production in the Upper Midwest. Depending on the arthropod pest species, however, there is either a complete lack of or extremely limited information on the species’ biology, ecology, and/or phenology. Knowledge of how these arthropod species interact with hazel plants is foundational to developing proper management. There are three major arthropod pests of concern that we have identified as economic threats to hazelnut production in the region: the hazelnut weevil (Curculio obtusus), the hazel stem borer (Agrilus pseudocoryli) and the filbert bud mite (Phytoptus avellanae). My dissertation research aims to develop pest management recommendations for the hybrid hazelnuts that will allow growers to be successful upon adopting them throughout the Upper Midwest for each of these pests individually and when considered together within an ecosystem.