Clover mites are very tiny mites that live and reproduce in the lawn, but now is the time they may be encountered as a household pest. During early summer and sometimes in the fall, clover mites wander or migrate and stumble into dwellings by mistake.
Clover mites feed on grasses and weeds, including clover but do no harm to turfgrass. They seem to be especially numerous in lawns with a heavy growth of succulent, well-fertilized grass. Clover mites do not bite or cause any damage in the house and are a pest only because of the annoyance of their presence and tremendous numbers.
In some situations it may be practical to reduce migration of clover mites into the house by removing the grass or vegetation and leaving a bare strip 18-24 inches wide next to the foundation. This grassless barrier can be mulched or planted with flowers and shrubs. Alternatively, a spray treatment can be applied as a chemical barrier on the soil and lawn in a band 10-20 feet wide around the house. The foundation and outside walls should also be sprayed. Successful chemical control requires a very thorough treatment. Materials labeled for this use include diazinon, Isotox, kelthane, and malathion. Application should be made as directed on the label and repeated after 2 weeks if mites persist.
Clover mites already indoors can be controlled using a household insecticide spray containing pyrethrins. It is advisable to use a vacuum cleaner to remove mites from indoor surfaces so as to pick them up without crushing them and creating an undesirable brown stain.
This article originally appeared in the April 26, 1996 issue, p. 57.