Creature Feature

Clover mites are a type of spider mite that feeds on grasses and weeds, such as clover. They are relatively large for a plant-feeding mite, and their front pair of legs are longer than the rest, which they hold forward like antennae. Eggs and newly hatched larvae are bright red, but, as they age, their bodies turn dark green. All clover mites are female and develop from unfertilized eggs. Clover mites use vertical surfaces, such as trees and buildings, to lay their eggs and molt.

Clover mites are cool-season mites that become inactive during warm, dry summers. High populations of clover mites can cause lawns and other plant leaves to turn brown and wilt. Structural invasions can also occur, usually in the spring, but also during the fall. They may be stimulated to migrate indoors after heavy rain, excessive heat, or a change in season. Because they leave a red stain when crushed, people may think they’ve been feeding on blood. However, clover mites are plant parasites, not animal parasites.

Clover mites usually enter buildings from the sides that get the most sun exposure and/or have a well-maintained, dense lawn. They are also common in new lawns. Their populations are often concentrated within 10 feet of vertical surfaces, so treating the bottom of these surfaces and out at least 10 feet is recommended. This depends on both what a pesticide label and applicator license allow. A turf and ornamental license is probably required to treat the base of trees and extended distances from structures. Indoors, clover mites tend to be found around windows, especially windowsills, which can be treated with a residual product that provides quick knockdown, so they don’t make it far into the structure.