These insects are tiny and red, you've seen them before and you've just noticed them on the concrete step you are sitting on. Don't panic -- these little critters are just a harmless cousin of the spider. They are a plant-eating arachnid known as the "clover mite."
Mites are eight-legged arachnids related to spiders and ticks. Only the size of a pinhead, they can be difficult to spot. View clover mites under magnification to see how they differ from other mites: They have longer front legs, which, due to their forward-facing position, are often mistaken for antennae. They come in a variety of colors, including greenish-brown, reddish-brown and orange, as well as the bright red shade seen in younger mites and mite eggs.
Clover mites are sap drinkers; they feed on grass and clover. They also demonstrate a liking for dandelion, strawberry and iris, and are repelled by flowers like marigolds, geraniums, roses and petunias.
Clover mites do not cause any harm, other than staining fabric if crushed. Even though they feed on grass sap, they do not injure the blades and pose no threat to your lawn. They do not transmit disease, and if they enter your house, they will not infest your pantry supplies.
Clover mites are typically found in grass but can find their way into your home through small foundation cracks or window-seal openings. Vacuum them up or damp-wipe carefully to avoid crushing them. Deter mites from entering by surrounding your house with a soil border that is free of greenery. If you add some plants for aesthetic purposes, ensure that they are widely spaced so that the mites don't use them to cross the soil. Inspect your home at ground level and seal any cracks you may find.