These yellow maggots, which may be up to 2–3cm/1in in length, are the larvae of the click beatle. Wireworms may take up to five years to reach the adult stage.
They eat the roots of vegetables and ornamental plants and burrow into bulbs. The holes that they create can form a point of entry for other pests and fungal diseases.
The most effective way of controlling the pest is by constantly cultivating the ground. This will expose them to predators such as birds. In addition, cultivated ground is far less attractive to the egg-laying females, and reinfestation is very unlikely.
Where crops such as potatoes or root vegetables have been grown on freshly cultivated land, they should be lifted rather than allowed to remain in the ground.