Here on the coast we enjoy the scenery of Spanish moss in many of our tress, which often times can contain chiggers. While biting chigger larvae climb vegetation to reach their hosts, they don't climb trees to nest in Spanish moss.
Spanish moss, however, may become heavy enough to break the branches supporting it or simply fall to the ground as birds tear it apart for nesting material. Once it's there, Spanish moss provides an ideal chigger-to-host ladder, so approach or handle it at your own risk.
If you have never experienced chigger bites, you are lucky. On a misery-per-pound basis, they are a lot worse than great white sharks and Bengal tigers put together.
Chiggers go by many names. In some areas of the country they are known as red bugs. There are several species, but they all belong to the genus Trombicula or Harvest mites. The tiny adult mite spends the winter near the soil in sheltered areas. In early spring they lay eggs, which hatch into the tiny six-legged parasitic larval form. These chiggers are less than 1/50 of an inch long.
The larval stage of chiggers is the only point in their life cycle where they feed on humans and animals. The tiny orange to red larva crawls around on the soil surface until a host is found. In addition to humans, they feed on small mammals, birds, reptiles and amphibians. I guess it is no wonder that frogs croak at night. They are really saying, “Scratch it, scratch it, scratch it.”
Chiggers prefer to attach themselves to areas of the human body where clothing fits tightly or the skin is thin. That makes ankles, waistlines, knees and armpits favorite feeding locations.
Contrary to what you may have heard, the tiny chiggers do not burrow into the skin. Instead, they suck fluids from the host. During this process they inject a digestive enzyme that liquefies the tissue of the host so that it is easily sucked up by the chigger. If unmolested, the chigger will finish feeding within three to four days and will drop from the host and mature into the nymphal stage.
Itching from chigger bites usually starts within four to six hours. Frequently the chigger is scratched away before it finishes feeding but the itching sensation will continue until the body neutralizes the digestive enzyme and repairs the damaged tissue. This could take as long as two weeks in some individuals. Scratching a chigger bite, of course, can also lead to secondary infections of the wound.
Chiggers are most often found in low lying damp areas that have lots of vegetation. Areas that are covered in small shrubs and small trees, including blackberry thickets, seem especially attractive to them. This means that one of the easiest methods of reducing chigger infestations is to clear brush and mow the area closely. This eliminates the protective cover and moisture that chiggers need to survive.
Chemicals can also be used for chigger control. Products that contain bifenthrin, cyfluthrin, deltamethrin, permethrin and others can be helpful. Granular soil insecticides may provide some control, as well. Always be sure to read and follow all label directions when using any pesticide to control chiggers.
Repellents are also helpful. Repellents that contain deet or permethrin may be used on clothes when venturing into chigger infested areas. Sulfur powder is effective when dusted on the clothing like pants legs and cuffs.
After visiting likely chigger habitat, be sure to take a thorough shower. A warm shower with plenty of scrubbing will dislodge many chiggers before they have a chance to feed. Check with your pharmacist for over-the-counter products that will help relieve itching. Surprisingly, studies have shown that meat tenderizer rubbed into the welt will help relieve itching.
Don’t fall victim to these tiny terrors this year. Control vegetation to eliminate habitat. Use repellents and, if necessary, chemical treatments to keep chiggers at bay. Maybe blackberry picking time doesn’t have to precede chigger scratching time.
Richard Evans is the extension agent for the Bryan County Agriculture and Resources. He can be reached at the Extension Office at 912-653-2231.