Hemp-pest
Guides
Aculops
Aculops is a genus of eriophyid mites comprising parasitic plant-feeding species. Several members are significant agricultural pests, including Aculops lycopersici (tomato russet mite) and Aculops cannabicola (hemp russet mite). The genus also includes species under consideration for biological control, such as Aculops ailanthii for management of invasive tree-of-heaven (Ailanthus altissima). Species diversity within Aculops remains incompletely documented, with new species continuing to be described.
Aculops cannabicola
hemp russet mite, HRM
Aculops cannabicola, the hemp russet mite, is a highly specialized eriophyoid mite and among the most serious pests of Cannabis sativa. First described from Hungary in 1960, it has since been detected across multiple continents including North America, Central Asia, and Europe, with its first Italian record in 2021. The mite causes distinctive rust-colored damage to leaves, curling of leaf edges, and russeting, and can reduce flower and seed production by 50-90%. It feeds on all plant parts including leaves, petioles, inflorescences of both sexes, and glandular trichomes, drastically reducing resin production. Control is notoriously difficult; the mite persists year-round in dry, warm habitats and complete eradication typically requires destroying all plants and sterilizing surfaces.
Phorodon
Phorodon is a genus of aphids in the family Aphididae containing at least two economically significant species: Phorodon humuli (damson-hop aphid) and Phorodon cannabis (cannabis aphid). The genus exhibits host specialization, with P. humuli feeding on hop (Humulus lupulus) and P. cannabis restricted to hemp and cannabis (Cannabis sativa). Both species are recognized agricultural pests in their respective cropping systems. P. humuli has been extensively studied for insecticide resistance mechanisms involving elevated esterase activity, while P. cannabis has emerged as a concern in the expanding North American hemp industry following legalization.