Wireworm

Wireworms are the larvae of click beetles (family Elateridae), a large group with hundreds of species across North America and Europe, several of which, including species in the genus Agriotes, are commonly encountered in gardens and farm fields. The name refers to the larva's tough, wire-like, cylindrical body, which is far more durable than the soft grubs of many other beetle families.

Unlike most beetle larvae, wireworms spend an unusually long time in the larval stage, often two to five years depending on species and conditions, living entirely underground where they feed on seeds, roots, and below-ground stems of a wide variety of plants.

Because of this extended larval period spent feeding on planted seeds and root crops, wireworms are a well-known and closely monitored soil pest in agriculture, particularly affecting cereal grains, potatoes, and other root vegetables.

• Body is slender, cylindrical, and hard-shelled, with a smooth, shiny yellow-brown to orange-brown surface
• Reaches about 1.5-2.5 cm (0.6-1 in) in length depending on species and age
• Has three pairs of short, small legs near the head and a distinct, slightly flattened head capsule
• Segments are uniform in width along most of the body, giving it a wire-like appearance that distinguishes it from the C-shaped, soft-bodied grubs of scarab beetles
• Found in soil rather than on foliage, usually only visible when digging

Found in soil across temperate regions of North America and Europe, particularly in grasslands, pastures, and cultivated fields that were previously in sod or grass cover. Wireworms are most active in the upper layers of soil during cool, moist conditions in spring and fall, moving deeper during summer heat and winter cold.

Wireworms feed underground on germinating seeds, roots, tubers, and below-ground stems, a diet that gives them their status as a soil pest of cereal crops, potatoes, and other root vegetables. They move vertically through the soil profile in response to temperature and moisture, staying closer to the surface in mild, moist conditions and retreating deeper during extremes of heat, cold, or drought. As soil-dwelling detritivore-herbivores, they are part of the broader soil food web and are preyed upon by ground beetles, birds, and other soil-foraging predators.

Adult click beetles lay eggs in soil, usually in grassy or weedy areas, in late spring or early summer. Larvae hatch and begin an unusually long developmental period underground, often spanning two to five years and multiple instars, during which they feed intermittently on plant material. When fully grown, the larva forms a small earthen cell and pupates, typically in late summer, before emerging as an adult click beetle the following spring. Adults are relatively short-lived compared to the extended larval stage.