Wireworms/Click Beetles

Common: Wireworms, Click Beetle

Scientific: Melanotus fissilis, Limonius spp.

Many species in the order Coleoptera, family Elatoridae.

Crop Hosts: Particularly damaging to corn and small grains, plus potatoes, onions, peas, sugarbeets and many garden crops are attacked.

Identification and Life Cycle: The winter is passed in the ground in the larvae or adult stage. Adults emerge in early spring. They are "hard shelled," dark-colored beetles. The females burrow into the soil and lay eggs on the roots. The adult lives 10 to 12 months. The larvae hatching from these eggs spend from 2 to 6 years in the soil feeding on the roots. The larvae change to naked, soft pupa and in a few weeks to the adult. The adult remains in the soil until the following spring.

Geographical Distribution: Throughout North America.

Damage and Treatment: Crops that are attacked by wireworms often fail to germinate since the insect eats the germ of the seed. In other cases the crop may germinate well but a later attack will reduce stand and lower plant vigor. Bulbs and tubers are tunneled and scarred, making a large part of the crop unmarketable. Planting crops into sod ground should be avoided.

Treatment should be made when insect populations and/or damage levels reach economic thresholds. Refer to local University Extension Pest Management Guidelines for specific state thresholds.