Short answer: If it bites you, it is not a clover mite. Clover mites (about 0.8 mm, reddish-brown, very long front legs) crawl over sunny walls and windowsills in spring and fall and never bite. Spider mites are even smaller, stay on plant leaves and spin fine webbing. Chiggers are almost invisible larval mites (about 1/150 inch) that you only notice from itchy bites around ankles and waistbands after walking through grass. Bed bugs are much larger insects — 5–7 mm, the size of an apple seed, with six legs — that hide in mattresses and bite at night. Where you find them and whether anyone is itching settles most cases in seconds.
Comparison table: clover mites vs spider mites vs chiggers vs bed bugs
| Clover mite | Spider mite | Chigger | Bed bug | |
|---|---|---|---|---|
| What it is | Plant-feeding mite (Bryobia praetiosa) | Plant-feeding mite (commonly the two-spotted spider mite, Tetranychus urticae) | Larval stage of trombiculid mites | Blood-feeding insect (Cimex lectularius) |
| Size | 0.75–0.85 mm (about 1/30 in); visible as a moving dot | Under 1/20 in (about 0.5 mm); a speck without a lens | About 1/150 in; needs magnification | 5–7 mm (3/16–1/4 in); easy to see |
| Colour | Reddish-brown to dark greenish-brown; smears red when crushed | Greenish or yellowish; red-orange forms common | Yellow-orange to red | Brown; reddish-brown and swollen after feeding |
| Legs | 8; front pair about twice as long as the rest | 8; no unusually long front legs | 6 (larva) | 6, plus two antennae |
| Where you find it | Sunny outside walls, windowsills, window frames, turf within about 10 ft of the house | Undersides of leaves on garden plants, shrubs and houseplants | On your skin after time in tall grass, weedy edges or brush | Mattress seams, box springs, bed frames, headboards, cracks near beds |
| Season | Spring and fall; gone in summer heat | Hot, dry weather, mainly summer | Warm months outdoors; peak in midsummer | All year, indoors |
| Bites people? | No | No | Yes — very itchy red bumps, often in clusters | Yes — itchy welts, usually on skin exposed during sleep |
| Damage | Red stains if crushed; silvery streaks in turf near walls | Pale stippling, bronzing and webbing on leaves; leaf drop | Bites only; no damage to plants or buildings | Bites, rusty blood spots and dark fecal spots on bedding |
Three questions that settle it
- Is anyone being bitten? No bites points to clover mites or spider mites. Bites after being outdoors in grass point to chiggers. Bites that appear overnight, with no outdoor exposure, point to bed bugs.
- Where are they? Crawling on sunny walls, window frames and sills, in spring or fall — clover mites. On leaves, with fine silk — spider mites. On the bed, in mattress seams or behind the headboard — bed bugs. Chiggers you almost never see; you find the bites.
- What do they look like under a lens? Eight legs with an extra-long front pair means clover mite. Six legs and antennae on a flat, apple-seed-sized body means bed bug.
Clover mites
Clover mites are about 0.75–0.85 mm long, reddish-brown to dark green-brown, with front legs about twice the length of the others, according to University of Florida IFAS Extension. They are all female, feed on lawn grass, clover and other plants, and are active in the cool weather of spring and fall. Large numbers climb sunny walls in search of cracks to shelter in, which is how they end up inside around windows. They do not bite people or pets, and Penn State Extension notes that those that get indoors cannot reproduce and die within a few days.
A handy size check: an adult clover mite is a little shorter than a single bed bug egg (about 1 mm). If what you are looking at is several times bigger than that, it is not a clover mite.
What to do: vacuum them up rather than crushing them (crushed mites leave red stains), seal gaps around sunny windows, and replace grass against the foundation with an 18–24 inch (45–60 cm) strip of gravel or bare soil. Full life cycle, lawn damage and treatment details are in our main guide to clover mites: identification, damage, prevention and control.
Spider mites
Clover mites and spider mites belong to the same mite family (Tetranychidae), which is why the names get mixed up. The difference is behaviour. Spider mites live on plants, mostly on the undersides of leaves, where a single colony can hold hundreds of mites. According to the UC Statewide IPM Program, adults are less than 1/20 inch long, look like tiny moving dots to the naked eye, and have an oval body with two red eyespots near the head. Their damage starts as a fine stippling of pale dots on the leaves, sometimes bronzing, then yellowing and leaf drop. Fine silk webbing is the giveaway. They thrive in hot, dusty conditions on water-stressed plants, peak from June to September, and can complete a generation in less than a week. They do not bite, and they don’t invade houses the way clover mites do, though they can build up on houseplants.
In lawns, the spider mite to know is the Banks grass mite. Colorado State University Extension describes it as more destructive to turf than clover mites, turning grass a bleached straw colour, and tied to dry conditions — steady watering, including in fall and winter where needed, is the main defence. See our guide to helping a lawn recover from drought.
What to do: hose the undersides of leaves with a strong spray of water, keep plants watered, and if needed use insecticidal soap or horticultural oil, covering the leaf undersides. Avoid broad-spectrum sprays: UC IPM notes that spider mites often become a problem after some organophosphate or pyrethroid insecticides are used, because those also kill the predatory mites that keep them in check. That is worth remembering if you spray a pyrethroid around the house for clover mites.
Chiggers
Chiggers are the six-legged larvae of trombiculid mites. Only the larvae feed on people and animals; the eight-legged nymphs and adults live in the soil and prey on insect eggs and small arthropods. Ohio State University Extension gives their size as about 1/150 inch, yellow to reddish, and usually too small to see without magnification. They wait at the tips of grass blades in humid, grassy fields, weedy areas and lawns and climb onto passing people and animals.
Two common beliefs are wrong. Chiggers do not burrow into the skin, and they do not suck blood. They inject saliva that breaks down skin cells, form a feeding tube called a stylostome, and feed on the digested skin. Bites concentrate where clothing is tight — around sock tops and shoe straps, waistbands, bra straps and armpits — and Ohio State notes the itching can last up to two weeks or more, and that numbers there peak from June through August. Clover mites never do this; if you have a line of itchy bumps around your ankles after gardening or mowing, it was almost certainly chiggers.
What to do: use a repellent containing DEET, picaridin or oil of lemon eucalyptus on ankles, legs and waist; wear long trousers and closed shoes in long grass; shower soon after coming inside (it removes chiggers still wandering on the skin); and wash the clothes on a hot setting. In the yard, keep grass mowed and clear brush and weedy edges, which makes the area less suitable for chiggers. For persistent itching or signs of infection, see a doctor or pharmacist.
Bed bugs
Bed bugs are insects, not mites, and are much larger than any of the others here. The US EPA describes adults as about the size of an apple seed (5–7 mm), flat and oval when unfed, brown to reddish-brown, swelling and turning redder after a blood meal. Young nymphs are translucent to whitish-yellow and hard to see. Eggs are pearl-white and about 1 mm long.
They hide in mattress seams, box springs, bed frames, headboards and cracks near where people sleep, and bite at night. The CDC notes they tend to live within about 8 feet of where people sleep, and that they are not known to spread disease — the harm is itching, lost sleep, anxiety and occasional skin infection from scratching. Signs to look for are rusty blood spots on sheets and mattresses, dark fecal spots, shed skins and, in heavy infestations, a sweet musty smell. Clover mites leave red smears too, but only where someone has crushed them, and usually on windowsills rather than bedding.
What to do: confirm with a physical specimen or clear signs, then act quickly. EPA’s do-it-yourself bed bug control steps include drying bedding and clothing on high heat, fitting sealed encasements on the mattress and box spring, vacuuming and immediately disposing of the sealed bag, steam at 130°F (54°C) or higher on seams and furniture, or holding small items at 0°F (−18°C) for three days. Reduce clutter, caulk cracks, and inspect every 7 days. For anything more than a small, early infestation, the CDC recommends a professional pest control company experienced with bed bugs. Garden and lawn treatments do nothing for bed bugs.
Other things people mistake for clover mites
A few more tiny creatures turn up in the same searches. The closest look-alike is Balaustium, a predatory mite that, according to UF/IFAS, matches clover mites in size and colour, also swarms over walls in large numbers, and needs at least a 20x hand lens to tell apart. Either way, vacuuming the ones indoors and sealing gaps around windows deals with the problem. Bright red, velvety mites several millimetres long in leaf litter are much bigger than clover mites and are also predators. Pale, jumping specks in damp soil or around sinks are springtails, not mites. Spiders in funnel webs on the lawn are grass spiders, which are beneficial predators. None of these need the treatments above.
Sources
- University of Florida IFAS Extension – Clover Mite, Bryobia praetiosa Koch (EENY 437)
- Penn State Extension – Clover Mites
- UC Statewide IPM Program – Spider Mites (Pest Notes)
- Colorado State University Extension – Clover Mites and Other Mites of Turfgrass
- Ohio State University Extension – Chiggers (ANR-0182)
- US EPA – Bed Bugs Appearance and Life Cycle
- US EPA – Do-it-yourself Bed Bug Control
- CDC – About Bed Bugs