Several species of wireworms are found in tobacco fields in South Carolina. Tobacco wireworms and the southern potato wireworm are the only two species of importance to tobacco in this state. The adults, known as "click beetles," are fairly distinguishable from one another. However, the larvae are quite hard to tell apart. Since life history and control practices are essentially the same, they will not be distinguished here.
Wireworm eggs are usually laid in the summer. When the eggs hatch, the larvae feed on a variety of different roots, overwintering in one of several larval instars, or stages. As tobacco is transplanted in the spring, wireworm larvae that are present feed on the newlyset plants, causing death or stunted, sickly-looking plants.
Damage due to wireworms varies from year to year. There may be serious damage some years and practically no damage in other years. Some damage, however, occurs nearly every year. More damage would be noticeable except that most tobacco farmers use a nematicide. This practice may give adequate control of wireworms as well.
Proper crop rotation may be of only limited value against wireworms. Some fields are problem fields year after year. Rotation away from such fields would be advantageous. On the other hand, rotation into such a field may result in considerable wireworm problems even if tobacco had never been planted there before.
Several different chemicals, and methods of application, may be used for control of wireworms. Unfortunately, control is usually on a preventive, rather than on an as-needed basis. Since the list of labeled products is constantly changing, and since available products varies from state to state, there will be no mention of specific products. With all insecticides, read and follow label instructions carefully.