We've already had calls about invading clover mites during recent unseasonably warm temperatures. Watch for this tiny pest coming inside around windows and doors, especially in areas where the sun warms the house. Clover mites have a preference for well-fertilized fescue turfgrass, so homeowners who have this type of turf may experience more recurrent clover mite infestations. The clover mite is an eight-legged relative of spiders and ticks. It is slightly smaller than a pin head and has a reddish-brown body. They have an unusually long pair of front legs, which distinguishes them from other mites (Figure 1). These tiny mites are brick-red; they come into homes through extremely small spaces around windows. Clover mites do no damage or injure humans. They cannot survive inside. Outdoors, they feed on turfgrass and other plants, but do not seem to cause any damage.
Effective outdoor control means preventing entry into buildings in the spring or the fall. The best way to prevent entry is to remove grasses and weeds in a three-foot strip around foundations, although mites may cross mulch and pea gravel to enter the home anyway. A chemical barrier outside the home may help reduce or prevent infestations inside the home. Treat five to ten feet out from the base of the foundation and a few feet up on the walls. Successful chemical control requires a very thorough treatment and may need to be repeated because many products on the market are short-lived. Treat when daytime temperatures will be at least 60º F because chemical effectiveness may be reduced with cooler temperatures.
Indoors, clover mites are best controlled with a vacuum cleaner. Avoid crushing or smearing the mites, especially on fabrics, because they may leave a red stain. It is not recommended to use chemicals indoors for clover mites. A vacuum cleaner works just as well and eliminates pesticide exposure. Whitney Cranshaw, Colorado State University entomologist, suggests putting a fine layer of dust around windows, in cracks, and other areas where clover mites may enter. Try using talc-containing baby powder, diatomaceous earth, or even baking soda. The mites coated with the fine dust will die in the barrier. Clover mites are so tiny they stick easily to almost any type of sticky tape. Place double-sided masking tape on window sills or other areas where mites are entering to catch the tiny mites as they cross the tape. When the tape becomes filled with mite bodies, simply peel it up, throw it away, and replace, if needed.