Cyclamen mite
Steneotarsonemus pallidus (Banks)

Description:

The cyclamen mite is extremely tiny and not visible to the naked eye. When mature it measures only about 0.001 inch long. Mature mites are pinkish orange and shiny. The hind legs are thread-like in the female and grasping or pincer-like in the male. At low population densities, cyclamen mites are usually found along the midvein of young unfolded leaves and under the calyx of newly emerged flower buds. At high population densities, these mites can be found anywhere on nonexpanded plant tissue.

Biology and damage:

The cyclamen mite requires a high temperature and humidity environment, and is therefore, more of a pest in greenhouses. However, in the field, cyclamen mites survive by residing within the protected folded leaves and sometimes blossom buds of strawberries. Leaves heavily infested with cyclamen mites become severely stunted and crinkled, resulting in a compact leaf mass in the center of the plant. Feeding may also result in flower withering and poor fruit production.
Cyclamen mites are primarily pests in second year plantings. Eggs are translucent and comparatively large. Adult females lay about 90 eggs, 80 percent of which develop into females. During summer, newly hatched mites develop into mature adults within 2 weeks. Populations build rapidly soon after they begin to infest a field. Cyclamen mites overwinter as adult females in the strawberry crown.

Field scouting/monitoring:

According to California state guidelines, in the field, monitor newly unfolding leaves and treat when you find 1 cyclamen mite in 10 leaves

Management:

CHEMICAL CONTROL
The cyclamen mite is extremely difficult to control by means of chemicals because the mite is resistant to many of the comercial insecticides, and because of its location within unfolded leaves on the plant. Hot-water dips have been used for years to treat for this pest (Schaefers 1981). When plants are known to be infested, treat them in hot water at 100 F for 30 minutes before planting. In nurseries, early season control before plant canopy closes over is critical.
Virginia spray guidelines
California guidelines

BIOLOGICAL CONTROL:
Two natural predatory mites, Typhlodromus bellinus and Typhlodromus reticulatus, are efficient predators, but seldom provide economic control. The sixspotted thrips can also be an important natural enemy when present.

CULTURAL CONTROL (California):
Cyclamen mites can easily be transferred from one location to another by pickers, pollinators, birds, and equipment, including strawberry freezer trays. It may be worthwhile to dip trays in a hotwater bath to prevent infestation (UC-Davis). Infested nursery plants are the major source of this pest in strawberry production areas; be sure to use uninfested nursery stock. When plants are known to be infested, treat them in hot water at 100 F for 30 minutes before planting. Avoid second year plantings in problem areas.