If you have ever been out in the woods or an open field in spring, summer or fall, you may have gotten chiggers around your waistband or on your ankles. They leave red, itchy bumps on your skin.
Chiggers are the larvae of mites belonging to the suborder prostigmata, commonly called harvest mites or scrub mites. Like ticks and spiders, mites go through three biological stages in their life cycle: They begin as eggs, hatch as larvae, develop into nymphs and finally become adults. Nymph and adult harvest mites feed mostly on plant life and don't bother people or other mammals, but in the larval stage, many of the species in the prostigmata suborder are parasitic. After a parasitic chigger hatches, it finds a good position on tall grass or other vegetation so it can spring onto a passing animal. When it finds an animal, it attaches to the animal to gather the protein it needs to grow into the nymph stage.
Chiggers do not burrow under your skin, as many people believe, nor do they feed on animal blood. They actually feed on the fluids in skin cells. To get the fluids, they attach themselves to a skin pore or hair follicle and inject a digestive enzyme that ruptures and liquidfies the cells. The enzyme also hardens the surrounding skin tissue, forming a sort of straw for sucking the skin cell fluids. The whole process irritates the skin, causing an itchy red bump that continues to cause discomfort for several days. Chiggers are only about 1/50th of an inch (0.5 mm) in diameter and so are almost too small to be seen with the naked eye. This invisibility is the reason so many people believe chiggers burrow under the skin.
You might encounter chiggers in any number of environments, but they are especially concentrated in damp areas with a lot of vegetation. They are attracted to concealed, moist conditions on hosts, too, so they tend to attach to skin under tight clothing, such as socks and underwear, or in concealed areas of the body, such as the groin and the armpits. One way to decrease the chance of chigger bites is to wear loose clothing when you're in the woods or other infested areas. You should also take a shower as soon as you get home from an outdoor expedition, to remove any chiggers before they attach to your skin.
In North America, chiggers don't spread any diseases to humans, but chigger bites can get infected. You should keep the irritated area clean and refrain as much as possible from scratching. In other parts of the world, chiggers may pose a more serious threat. In some areas of Asia, for example, certain chigger species carry the disease scrub typhus. If you spend a lot of time outdoors, check an insect and spider field guide to find out what sort of chiggers are in your area.
One commonly known remedy for chigger bites is to apply nail polish to reduce itchiness. This does not kill the chigger or treat the bite in any way. It simply seals the area off from the air, which keeps the sore from itching so badly. If you want to apply something to relieve itching, it's much better to use a salve or cream that contains antihistamines (Caladryl or hydrocortisone salves are the most common). Like nail polish, these treatments will seal the bite from the surrounding air, but they will also help to prevent infection. If the welts continue to irritate you for more than a couple of weeks, they might be infected and you should see a doctor.
Chiggers are prevalent throughout the southern part of the United States. They are red, and look like a tiny spider or clover mite, and smear red when crushed. Chiggers are different from both spider and clover mites in that they like to feed on flesh. They will readily bite dogs, cats, livestock, birds, people or just about any animal they can find. Chiggers live on the ground, around shrubs and plants, or anywhere vegetation is able to protect them. They prefer shade and moist areas, but will forage for food great distances if needed.
Unlike most small mites, chiggers are able to move quickly. They are able to sense movement and detect any food source from a great distance. Pets will get chiggers simply walking throughout the yard; people can get them playing golf, working in the garden or during a picnic. Chiggers spend the winter lodged in the soil a few inches deep. When spring arrives, adults emerge to lay eggs in the same areas they hibernated. Eggs will hatch in a short while to release the larval stage. This is the stage which feeds on mammals. It requires flesh and will feed on just about any mammal available. Once a target is found, the young chigger will attack. First, it will crawl over shoes, socks and pants attempting to find meat.
Chiggers are small enough to fit through the mesh of many fabrics. This enables them
to penetrate socks or pants quickly. Once on the skin, they will try to locate a place
where they feel secure. This is usually under socks, around the waistband of underwear or anywhere clothing is tight. At this point, they will either puncture the skin or use hair
follicles to get food. Chiggers will then inject the special fluid enzyme which liquidfies the flesh as mentioned above, enabling the chigger to "suck" it's meal. During this time, you would expect to feel an itch where they are feeding. Their digestive fluids usually irritate our skin and creates a red blotch. In a day or two, this area may develop a blister.
The best product to use on the bite is chigger bite ointment. This ointment will take the "itch" away and promote healing. Since chiggers will readily climb over clothing to
get to your flesh, use permethrin concentrate on shoes and pants. Permethrin is odorless, easy to mix and works well at keeping many pests away. Mix some up in a small spray bottle for spraying while afield. Be sure to use it on shoes and pants to keep them off. Apply as needed.
Though the aerosol is easy to use the concentrate will prove to be more cost effective if you will have to be using a lot over time. Once they feed, larva will drop off the host
and go through a period of development where they become adults. By the fall, they will
be active again. Now fully mature adults, they will seek organic matter on which to feed and nest. Beds of chiggers will now form as fall becomes winter. Adults will then dig into the ground and overwinter protected from freezing temperatures and rain. In the spring, the cycle will start all over again.
In some regions, warm temperatures and high humidity allow the chigger to complete two cycles a year. This creates two "feeding seasons" during the year. One in the spring and then again in late summer to fall. Depending on the year, it may feel as though they are active all the time. Other seasons may prove to have little chigger activity giving the impression they have disappeared. Rest assured they will be back!
Chigger control starts with identifying where they are nesting. This is typically around the
home in pine straw, wood chips, mulch areas, grass, overgrown wild areas, briar patches, or anywhere ground cover is thick. English ivy, poison ivy and junipers will all provide great protection for nesting chiggers. Since these locations may be all over the property, chigger control is best done by treating everything. Treatment is easy when using the right product.
Cyfluthrin works well on chiggers. It's one of the newer active ingredients so chiggers have not had a chance to develop resistance just yet. Cyfluthrin goes a long way and it
is important to treat as much of the local area as you can. Use a hose end sprayer and
be sure to get grass, thatch, pinestraw, mulch and plants saturated. Cyfluthrin is perfect for this application; it has a low odor, won't hurt plants or trees and is very safe around people and pets. If your property is adjoined by a wild area, be sure to apply material there. Since chiggers migrate, treating these borders will provide some extra protection. Treatments should be done once a month for two months in the spring and then once in the fall. This schedule will keep your property free of chiggers for at least a year.
Watch populations the year following your first application. You may be able to skip a year before having to treat again, but in general property which has an infestation once is
likely to get one again. To prevent this from happening, once a year applications will
prove to be a good investment. If you are finding chiggers inside, use the Cyfluthrin in a sprayer to treat baseboards, crawlspaces or other areas where populations are suspected to be living. If the original population was immediately adjacent to the home, outside turf treatments should be made first being sure to spray foundations as well - even if you don't think any are present there.
You need to treat foundations to prevent traveling chiggers from finding their way into the home. Once inside they can be a nuisance to control generally needing several applications. This happens because they don't find a lot of comfortable habitat in the home so they forage and seek new places more readily. If you treat thoroughly they are easy to control; if you miss some areas there is a risk they will move there in a short while.
Chiggers are a flesh feeding pest which can ruin picnics, back yard get togethers or gardening activities. Their bites are irritating, itch and will persist. Treat bites with chigger bite ointment for relief. Apply Permethrin Concentrate Spray to repel chiggers when going afield where chiggers live. Around the home, control them quickly with Tempo. Two or three treatments the first year will get the population under control and followups of once a year should prevent them from returning.