Wireworms are the larvae of click beetles. There are several species that live in North America. The larvae are slender and hard, smooth jointed, wire-like bodies. They dwell in the soil for 3 – 5 years; feeding on and damaging young root systems and seeds that are recently germinated. They consume live roots, seeds, cereals, or grasses and they are especially fond of potatoes and sugar beets. The beetles are hard-shelled, rectangular, and elongated. The adult beetles over-winter in the soil and emerge in April and early May. From May to June the females deposit anywhere from 200 – 400 eggs in the soil. They do not become active until the air temperature is over 50° F.
Fields that have an infestation, will likely have all life stages present. To determine if there are wireworms in your garden or field, Bait Balls are the recommended method for trapping and determing the extent and location of the pest.
Bait Ball Recipe – Makes 1 Bait Ball:
- Mix 1 to 1 ½ cups of wheat flour or oatmeal, 2 tablespoons of honey, and slowly add up to 1 cup of water.
- Mix in the water until you can make a ball with the mixture.
- Put the ball in the ground or in a mesh bag(leftover mesh bags from produce work well).
- Bury the balls in 4 – 6" deep holes and mark them with stakes or flags.
- Use 20 bait balls for every 1 acre of land – space them evenly through the acre.
- Apply Steinernema carpocapsae nematodes. Nicknamed NemAttack, the Sc nematodes are the most effective control for wireworm.
- A soil drench with Pyrethrins is also an excellent control for wireworm.
For more information about beetles please check out our Beetle Control page.
Photo courtesy of Clemson University Department of Entomology, Soils & Plant Sciences, Cooperative Extension Service.