Pests Beneficial Organisms Insect-Transmitted Diseases Management Options Other Resources Contact a Specialist Two-spotted Spider Mites — Tetranychus urticae Two-spotted spider mite is common on weeds and many crops.   Several things can contribute to spider mite outbreaks in potato:   Non-selective pesticides, such as pyrethroids Proximity to certain crops such as corn, alfalfa, hops, and mint, which tend to harbor mites Proximity to dusty roads Hot, dry weather   Scouting for mites should begin in late June or early July. A hand lens is required for field recognition.   If a miticide is used, it must be applied early in the infestation — miticides are not capable of controlling intense infestations.