author(s)
John M McPartland and Zahra Sheikh

abstract
Plant-based pesticides are gaining attention as safe, effective, eco-friendly alternatives to synthetic pesticides. We conducted a literature search regarding the use of hemp (Cannabis sativa) as a plant-based insecticide, miticide, or repellent. The search yielded 88 publications, which we grouped into five types of applications: companion planting (17 articles), the use of harvested plant material without any extraction (25 publications), aqueous extracts (20 publications), essential oil extracts (EOs, nine publications), and solvent extracts (17 publications).Few studies chemically analyzed the contents of their extracts, and most studies lacked control comparisons. EO studies were the most rigorous, and yielded the best results. Results with solvent extracts showed moderate efficacy, but little better than aqueous extracts, which lacked tetrahydrocannabinol (THC). Collectively, the studies suggest that EOs (terpenoids) are the primary Cannabis constituents responsible for arthropod deterrence. THC exerts nominal deterrence, but is toxic to insects. Mechanisms of action are discussed.