Clover mites are common household pests that can appear in large numbers, often causing concern for homeowners. This article aims to clarify the characteristics of clover mites, their impact, reasons for their appearance, and effective control strategies. Understanding these aspects can help in managing their presence around your home.
Identifying Clover Mites
Clover mites (Bryobia praetiosa) are tiny arachnids, related to spiders and ticks, that are barely visible to the naked eye. Adults typically measure between 0.03 and 0.033 inches (0.75-0.85 millimeters) long, smaller than a pinhead. Their bodies are oval-shaped and range in color from reddish-brown to dark greenish-brown, sometimes appearing reddish-green or olive green depending on their diet.
They have eight legs, with the front pair notably elongated and often mistaken for antennae. These mites move slowly and deliberately. They are commonly observed crawling on surfaces near windows, walls, and doors, especially on the sunny sides of buildings. When crushed, they leave a reddish-brown stain from their body pigments, not blood.
Understanding Their Impact
Clover mites are nuisance pests, not harmful. They do not bite or sting humans or pets and are not known to transmit diseases. They do not feed on human blood or infest food, clothing, or household furnishings.
Their primary concern is leaving reddish-brown stains when crushed. This pigment can be difficult to remove from light-colored surfaces such as walls, carpets, drapes, and furniture. While they feed on the sap of plants, including grasses and clovers, they rarely cause significant damage to indoor plants or garden crops. Heavy feeding on turfgrass can occasionally lead to a silvery discoloration, but this is usually not severe.
Why Clover Mites Appear
Clover mites infest homes seeking shelter from unfavorable outdoor conditions. They primarily feed on the cell contents of various plants, including turfgrasses, clover, dandelion, and some ornamental flowers. Lush, well-fertilized lawns are particularly attractive to them, providing an abundant food source.
They migrate indoors, usually in late spring, early summer, and fall. This occurs when outdoor temperatures become too hot or cold, or when food sources dry up. They enter buildings through tiny cracks and openings around windows, doors, foundations, and utility lines, often congregating on the sunny sides of homes. They can reproduce rapidly, with females laying up to 70 eggs without mating, contributing to large population surges.
Clover Mite Control Strategies
Control involves preventive measures and direct removal. Prevention is often most effective. Creating an 18 to 24-inch grass-free zone around your home’s foundation significantly reduces their access. This barrier can be left barren or covered with materials like gravel, pea gravel, or mulch, which mites find difficult to cross.
Sealing entry points is also important. Inspect and caulk cracks around windows, doors, and the foundation, ensuring weatherstripping is installed. Avoiding over-fertilization of lawns and removing leaf litter near the foundation can also help deter them.
When mites are found indoors, non-chemical methods are preferred to avoid staining. Vacuuming with a crevice tool is effective; immediately seal and dispose of the vacuum bag outdoors to prevent escape. Wiping surfaces with a damp cloth or soapy water can also remove them without crushing. For severe outdoor infestations, professional pest control or the application of an outdoor insecticide labeled for mites around the foundation may be considered.