D3427: Insect diversity and succession on industrial hemp (Cannabis sativa L.) in North Carolina, and the impact on crop performance

Recent legalization of industrial hemp (Cannabis sativa L.) in the USA has resulted in its cultivation over a much wider geographic area. As production increases, knowledge on the insect communities associated with hemp will be critical to understanding beneficial and pest insects that affect the crop at different phenological stages. An entomological study was conducted in 2021 at North Carolina A&T University Research Farm on four hemp cultivars (CFX-2, Canda, Joey and Henola). Weekly insect estimates were made using direct (visual) counts, pan and pitfall traps and vacuum sampling. The goal was to 1) determine insect abundance and diversity on hemp and 2) assess the impact of pests on yield. The results indicate that several insect pest groups, including leafhoppers, Japanese beetle, brown marmorated stinkbug, leaf-footed bug, tarnish plant bug, flea beetle and cucumber beetle and beneficial insects such as the honeybee, bumble bees, sweat bees, hoverflies, big-eyed bugs, and lady beetles were recorded on all the hemp cultivars. During the first three weeks of sampling leafhoppers were the most prevalent. By week five, there were more bumblebees, honey bees and big-eyed bugs. Insect diversity and abundance varied weekly among the cultivars. Joey recorded the highest seed yield. Findings from this study can be used to better understand how insects may affect this grain crop. Understanding the role of insect pests and beneficial insects will lead to mitigation plans as part of a robust management strategy for increasing the yield and quality of hemp crop.