The Walgenbach Lab focuses on solving pest management problems for the tree fruit and vegetable industries in North Carolina's southern Appalachian and piedmont regions. Its overall goals are to develop and implement comprehensive pest management programs that are economically viable and minimize risk to the environment, farmworkers, and non-target organisms. Recent research has addressed a variety of issues, ranging from the broad management of pest complexes on a regional level to studying toxicity and behavioral responses of isolated laboratory strains of insects and mites. Most projects have short- to near-term implications. The lab takes pride in implementing new research into ongoing pest management programs by working closely with the grower community, county and regional extension personnel, and the crop protection industry. Some of our recent projects include:

The western flower thrips (Frankliniella occidentalis) is a key pest of NC tomatoes and peppers, transmitting tomato spotted wilt virus as well as directly damaging fruit. Insecticide-resistant populations are becoming more common in areas with intense tomato or pepper production, leaving few options for chemical control. We are currently researching the spread of resistance, identifying pesticides with new modes of action, and developing cultural practices such as reflective mulches and crop rotation that can better manage local populations of western flower thrips.

Many of today's IPM protocols rely on trap-capture and degree-day models that were developed decades ago. As the climate has changed and insect populations have evolved, these protocols need to be reevaluated and updated to fit current realities. Our lab is part of a multi-state coordinated effort to test existing protocols and new methods for managing codling and oriental fruit moth, plum curculio, San Jose scale, brown marmorated stink bug, and other common pests of Eastern orchards.

The brown marmorated stink bug (BMSB, Halyomorpha halys) is an invasive crop and nuisance insect that has become a regular pest of NC agriculture. After being detected in NC in 2009, it spread rapidly throughout the mountain and piedmont regions of the state, appearing first in structures and urban landscapes and later feeding on tomatoes, peppers, corn, apples, peaches, soybeans, and a variety of other crops. For several years our lab was part of a team of more than 50 scientists in the US working to understand BMSB biology in North America and to devise management strategies for a diversity of crops. Ongoing projects include BMSB population monitoring, pesticide screening, and biological control. Visit our BMSB homepage for more details.

Biological control with insect predators and parasitoids can reduce pesticide use, which in turn reduces costs and protects human health and the environment. Our IPM work with narrow-spectrum insecticides and mating disruption has helped encourage natural biological control for years. More recently we have begun investigating the use of a predatory mite for local control of twospotted spider mites and various species of wasp parasitoids for landscape-wide control of brown marmorated stink bugs.

Permanent research plots of apple and peach trees, as well as annual plantings of tomatoes, peppers, collards, and other vegetables, allow for extensive insecticide comparisons on the Mountain Horticultural Crops Research Station. Experimental materials and spray programs can be compared to existing products to determine their viability in field conditions without jeopardizing the crops of commercial operations. The Walgenbach Lab has conducted at least one or two insecticide trials every season for the past 30 years.

The Walgenbach lab has been conducting field studies on pheromone-mediated mating disruption of tortricid pests of apples in NC for more than 20 years. The adoption of mating disruption for both codling moth (Cydia pomonella) and oriental fruit moth (Grapholita molesta) by the grower community has been an important part of managing resistant populations. Among apple growers using mating disruption on an annual basis, codling moth and oriental fruit moth populations are consistently lower, and biological control of European red mite and apple aphids is generally enhanced, compared to growers not using mating disruption. In recent years, we have begun testing mating disruption for diamondback moth in brassica fields in eastern NC.

Two species of ambrosia beetles, Xylosandrus crassiusculus (granulate or Asian ambrosia beetle) and X. germanus (black stem borer), have been pests of apples in newly planted high-density orchards since about 2015. In North Carolina there is a possible relationship between ambrosia beetle attack and rapid apple decline (RAD), a phenomenon where otherwise healthy-appearing young trees suddenly die. This is a cooperative project among the NC apple team (entomology, plant pathology and horticulture) and a multi-institutional working group. Research is focusing on the physiology of tree stress and beetle response to stress, as well as the ecology and management of ambrosia beetles as they relate to apple orchards.

• Walgenbach Lab Home
• People
• Walgenbach Lab on Facebook

Additional Resources

• Apple Pest Management
• Vegetable Pest Management
  • Benefits of Applying Insecticides with Drip Chemigation
• Brown Marmorated Stink Bug in NC
  • Biological Control of Brown Marmorated Stink Bug
• Biological Control with Predators and Parasitoids
• Intergrated Orchard Management Guide for Commercial Apples in the Southeast
• Southeastern US Vegetable Crop Handbook
• NC Agricultural Chemicals Manual
• Compendium of Apple and Pear Diseases and Pests (APS Press)
• Management of Brown Marmorated Stink Bug in US Specialty Crops: Annual Reports
• BMSB Monitoring in NC: 2019; 2018
• Walgenbach Lab Annual Reports (2003-2015)
• Department of Entomology and Plant Pathology at NC State University

Entomology Dept.
Mountain Horticultural Crops Research & Extension Center
455 Research Drive Mills River, NC 28759
Phone: (828) 684-3562
Email: jim_walgenbach@ncsu.edu