Explosive. That’s one way to describe the speed at which mite infestations in crops can develop under the right conditions. Those conditions are hot, dry weather—a common occurrence on the High Plains. A spider mite female, for example, can produce 300 offspring during her 30-day lifetime, enabling a mite population to grow from a few individuals to millions rapidly.
The two primary mite pests in the High Plains are the Banks grass mite and the two-spotted spider mite. Heavy infestation in beans can cause leaf loss and even the death of the plant, while mites can cause lighter test weights in corn.
Penn State University Extension entomologists note that most mite populations first develop on grasses and other plants found along the margins of fields. The preproductive female mites then use a silken thread as a kite to migrate into the field1.
Because mite populations can build so quickly, regular scouting of field borders when conditions favor mite development is the best way to catch outbreaks before mites can move further into the field.