The vegetable weevil (Listroderes obliquus).This introduced pest occurs in most parts of the State and in both the grub and adult weevil stages may do considerable damage to a wide variety of vegetable and flower plants. In addition, they feed on many weeds, being especially partial to capeweed, marshmallow and similar succulent plants.

During late autumn and through the winter beetroot, carrots, lettuce, parsnips, potatoes, radishes, cabbages, turnips, stocks, calendulas and similar plants are attacked by the larvae. At first the leaves show numbers of small irregular holes, especially those in the crowns of the plants. Later these become more extensive and larger and the foliage may be devoured almost completely.

Root crops such as carrots, turnips, etc., may be attacked below ground level and the fleshy roots gouged or furrowed. In the adult stage during the spring the weevils may be very destructive especially to potatoes and tomatoes, feeding heavily upon the foliage and stems.

Both weevils and grubs feed mostly at night and during the clay shelter at the bases of the plants under clods.

Crops such as beans and peas, pumpkins and squashes, and cereals like oats and barley, are not attacked.

The adult weevils lay their eggs on the soil at the base of the plant and these eggs hatch in from 2-4 weeks. The larvae appear 3-4 weeks after the first autumn rains. These larvae feed on the plants, usually on the under-surfaces of the leaves, for 4-6 weeks. After they are fully fed they construct earthen cells in the
soil, 1-3 inches below the surface, and there they pupate. The adult weevils develop from these pupae and appear from about August onwards. They feed until about November and then remain inactive until the cooler autumn weather when they begin to lay eggs.
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