Recipient Organization
University of Maryland Eastern Shore
11868 College Backborne Road
Princess Anne,MD 21853
Performing Department
Agriculture
Non Technical Summary
With the passage of the 2018 U. S. Farm Bill that removed hemp from the Federal list of controlled substances and declared it a distinct crop from marijuana, the emergence of hemp (Cannabis sativa) grown for CBD (cannabidiol) products as a potential crop has been sudden and dramatic. Hemp acreage expanded at a rapid pace in the Delmarva region. However, due to the long moratorium on C. sativa in the United States, there is a serious lack of production knowledge for hemp and even less for pest management. Regarding available literature concerning insect pests present in North American hemp, information is dated, not region specific, and does not address effective management methods. This proposal will provide information about the key insect pests of hemp in the Delmarva region and their possible biological and chemical control methods.
Animal Health Component
60%
Research Effort Categories
Basic
20%
Applied
60%
Developmental
20%
Goals / Objectives
With the passage of the 2018 U. S. Farm Bill that removed hemp from the Federal list of controlled substances and declared it a distinct crop from marijuana, the emergence of hemp (Cannabis sativa) grown for CBD (cannabidiol) products as a potential crop has been sudden and dramatic. Hemp acreage expanded at a rapid pace in Virginia in 2019 and is estimated to greatly increase in Maryland and Delaware as well. However, due to the long moratorium on C. sativa in the United States, there is a serious lack of production knowledge for hemp and even less for pest management. Regarding available literature concerning insect pests present in North American hemp, information is dated, not region specific, and does not address effective management methods.Objective 1. Determine the key insect pests and beneficial arthropods in hemp fields in Virginia, Maryland, and Delaware.Objective 2. Determine if pheromone trap catches of corn earworm moths can help predict larval infestations in hemp. Objective 3. Disseminate research findings to other researchers, Extension personnel, and hemp growers in the DelMarVa region.
Project Methods
Objective 1. Determine the key insect pests and beneficial arthropods in hemp fields in Virginia, Maryland, and Delaware. Based on surveys in Virginia over two years, corn earworm has demonstrated the greatest potential for crop injury, being particularly damaging to flower buds and seed heads. Moreover, numerous species of caterpillars, grasshoppers, and beetles chew hemp foliage, and the effects of this injury on the plant needs further study (Kuhar and Britt, unpublished). Similarly, seed feeding hemipterans, such as stink bugs including brown marmorated stink bug (Britt et al. 2019) and Lygus bugs, are regularly found in the crop, but injury potential remains unclear. In addition, an exotic species, Cannabis aphid, was found in abundance on hemp in VA; this was the first report of this species in the eastern U.S. (Cranshaw et al. 2018). This aphid species has not been recorded in Maryland or Delaware and its damage potential is unknown. Additional arthropod surveys on hemp in all three states will provide extensive information on the pest complex.Objective 2. Determine if pheromone trap catches of corn earworm moths can help predict larval infestations in hemp. Pheromone traps have been used for two decades to monitor corn earworm moth activity in soybean, sweet corn, and cotton. Their utility to help guide pest management in hemp has not been determined. In all three Delmarva states and in as many fields as we can sample, we will install Heliothis mesh traps baited with corn earworm pheromone and monitor them weekly from July to September to determine if adult trap catch correlates with worm/larval presence in the hemp fields. Hemp plants will be visually inspected for two-minute sample intervals and the number of larval H. zea will be recorded. A regression of weekly pheromone catch of adults on larval infestation will be made to determine the value of this sampling tool.Objective 3. Disseminate research findings to other researchers, Extension personnel, and hemp growers in the DelMarVa region. Each of the PIs on this project is heavily involved in Extension in the Delmarva Region, including giving presentations at several field days and meetings centered around hemp production in Virginia in 2018-19 and a hemp field day Maryland in 2019. These venues will undoubtedly continue and expand in numbers in 2020, and our work will very likely be presented at those meetings to help disseminate the research findings. Extension agents such as Kelly Scott (VCE, Montgomery County) will further disseminate information on the hemp grower's website.