Managing Corn Earworm in Hemp Field by Using Sweet Corn as a Trap Crop

Project Overview

Project Type: Farmer
Funds awarded in 2020: $14,895.00
Projected End Date: 03/31/2022
Grant Recipient: Wood Duck Landing Farm
Region: Northeast
State: Maryland
Project Leader:
Kelly Edwards
Wood Duck Landing Farm

Information Products


  • Agronomic: other


  • Education and Training: on-farm/ranch research
  • Pest Management: cultural control, integrated pest management, trap crops

    Proposal summary:

     Currently, there is no EPA-labeled pesticide or bio-pesticide in the U.S. for industrial hemp, and growers are facing challenges to manage insect pests and diseases. Additionally, Hemp producers indicate that target industrial hemp markets are sensitive to pesticide residue. Our farm has participated in the 2018 hemp pilot program. Dr. Simon Zebelo, from UMES, has identified most of the potential insect pests of hemp in our field. The most abundant and devastating pest was corn earworm (CEW). We had significant damage to the hemp flowers by CEW. CEW mainly dwelled and fed in between the flower buds, and it is difficult to see CEW until it causes visible damage. The CEW larvae contaminate the flowers with frass. We are proposing to develop a sustainable way of controlling CEW by using sweet corn as a trap crop. Moreover, in collaboration with Dr. Zebelo, we will evaluate if heavy insect infestation increases the D9THC beyond the legal limit (0.3%), there is literature that shows insect damage changes plant chemistry. The population of CEW and their damage will be measured by using pheromone traps and visual inspection, respectively. We anticipate that adjusting the ear forming sage of the trap crop with the flowering stage of hemp will significantly reduce damage by CEW. 

    Project objectives from proposal:

    Objective 1: To develop a sustainable way of controlling CEW by using sweet corn as a trap crop

    This project seeks to develop a sustainable way of controlling CEW by using sweet corn as a trap crop. Attractive sweet corn will reduce the insect population in the main hemp crop fields. CEW reported as the main pest of hemp in the northeastern states (Britt et al 2019). This study might benefit hemp growers all over the nation.

    Objective 2: To assess the impact of insect herbivore damage in the level of cannabinoids.

    This objective seeks to evaluate if the environmental factors such as insect damage increases the level of D9THC. The D9THC level for hemp (i.e. 0.3%) might be spiked up by insect herbivory, as result farmers might loss legal coverage under 2018 Hemp Act. This objective will provide info for educators, farmers and lawmakers.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.