David Robson: Dealing with chiggers

David Robson

While mosquitoes are as welcome as an ice storm, they also get blamed for things they don’t do.

Don’t get us wrong. Mosquitoes, particularly the females, bite, carry diseases and create unpleasantness beyond belief. But you can’t blame every bite on your body on mosquitoes.

The biggest case in point: chiggers.

Chiggers aren’t insects. They’re mites. Unlike the biting habits of April and early May buffalo gnats or summer mosquitoes, juvenile- or larval-stage chiggers do the biting. Adults are strictly vegans. Both male and female chiggers bite.

To confound you more, if you looked through a magnifying glass at the chigger that bites you, you would see it has six legs, just like an insect. But if you capture a chigger and watch it pupate into an adult, you would see it has eight legs, making it a relative to other arachnids such as spiders.

Chiggers are microscopic, about 1/50th of an inch across. They are blood-red in color naturally — in fact, a well-fed chigger will be more of a yellow color.

Our chiggers do not burrow under the skin. They insert their mouth parts into our skin pores, around hair follicles or folds in the skin. They are seldom able to pierce thick skin, so you’ll likely find chigger bites at the ankles, the back of the knees, around the crotch, under the beltline and under the arms. Chiggers will climb over clothing to reach a spot where they can insert their mouth part.

During summer, when folks are often in shorts or barefoot, a chigger-related injury is usually found at the ankles, usually with pinhead-sized red welts. Within a couple of hours, the itching and redness usually disappear. Severe infestations may take several days to go away.

The piercing doesn’t hurt, and most of us don’t feel it. But when the creature’s salvia reacts with our cells, it causes red welts and itching.

Chiggers like high humidity. Tall grass, vegetation and wooded areas are more likely to harbor the mites. Keeping your lawn mowed can help reduce their presence. Lots of trees, shrubs, shade plants and a moist environment will likely create an environment that’s ideal for the creatures.

Chiggers can remain on a body for three to four days, trying to finish a meal. In most cases, that doesn’t occur because we bathe or brush the creatures off as the itch causes us to scratch. If you prevent a chigger from finishing its meal, that’s the end of the creature. It can’t bite someone again and ends up dying. Justice.

Chiggers are constantly moving over the ground, praying they’ll find a bird or reptile, their primary food source. Humans are often an afterthought for chiggers. (War vets can talk about the notorious Asian chiggers, which feed primarily on humans.)

Because they are constantly moving, chiggers can cover your body quickly, looking for a piece of bare skin to settle into. They can be choosy, spending hours looking for the ideal spot.

Because men have thicker skin, they tend to have fewer bites than women or children. However, that doesn’t mean men are immune. A blood opportunity is a blood opportunity. The chigger just has to work harder.

Chiggers like temperatures between 77 and 86 degrees. They’ll just sit there when temperatures are below 60 degrees. They’ll die in the lower 40s. Surprisingly, they don’t like temperatures above 100.

If you are in a chigger-infested area, don’t wear shorts, sandals or short-sleeved shirts. Wear long-sleeved shirts, long pants, heavy socks, leather shoes and gloves. Tuck your pants into your socks. You won’t be a fashion plate, but you won’t get chigger bites.

Dr. Phil Nixon, University of Illinois Extension entomologist, suggests using mosquito repellents with DEET (sold as Off). Spray your exposed skin and the areas around your waistbands, cuffs, shoe tops and shirt buttons. If you plan on being outdoors for several hours, you may need to reapply the product.

Change your clothes and launder them when you get home. It’s would be good to take a shower and wash any hitchhikers down the drain.

Outdoors, you can spray your yard once with carbaryl or Sevin. This insecticide is a quick knock-down of all the chiggers. One application should take care of the area for the entire summer.

David Robson is a horticulture educator for the University of Illinois Extension. For more gardening information, go to