Damage. This beetle species is commonly found in grassland, but will attack most crops. Turf grass may be eaten away by the larvae (wireworms) resulting in dry areas of grass. The pest also bores through potatoes to produce characteristic narrow tunnels, while in onions, brassicas and strawberries the roots are eaten. In tomatoes, the larvae bore into the hollow stem.
Life cycle. The 1 cm long adult (click beetle) is brown-black and has the unusual ability of flicking itself in the air when placed on its back. The female lays eggs in weedy ground in May and June and the larvae, after hatching, develop over a four year period. Fully grown wireworms are about 2.5 cm long, shiny golden-brown in colour, and possess short legs (see Figure 14.7). After a three week pupation period in the soil, usually in summer, the adult emerges and in this stage survives the winter.
Control. Some amateur gardeners dig in green manure crops to lure wireworms away from underground roots and tubers. Professional growers may reduce serious damage to young crops by using a seed dressing containing tefluthrin.
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