Abstract
This chapter is intended to illustrate the process of diagnosing insect and mite damage with an emphasis on microscopic insects (such as leaf miners belonging primarily to Lepidoptera, Hymenoptera and Diptera, Phorodon cannabis, Aleyrodidae, Thripidae and stem borers) and mites (including Aculops cannibicola and Tetranychidae), as well as the hidden symptoms caused by them. Diagnosing an insect problem is different from insect identification. A hemp problem should be diagnosed as a type of insect damage first before any taxonomic identification of a suspected insect is performed. That said, growers can make a preliminary diagnosis based on insect population trends in the field and levels of plant damage observed, collect insect specimens of all available stages and submit them to a plant clinic for identification. The chapter also discussed arthropod pest management by preventing pest entry to indoor facilities, monitoring pests throughout production, planting barrier crops, eliminating alternative host plants for pests, trapping flying insects, use of natural enemies and applying alternative products.