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Vine Weevil



P_vineweevil1

Vine Weevil

Usually appear in

Spring to Autumn.


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Caused By:-     Several Beetles of the Genus Otiorhyncbus

Description

There are several species of Vine Weevils from the genus Otiorhynchus whose soil born larvae does great damage to a wide range of plants, shrubs and trees especially Azalea, Camellia, Cyclamen, Begonias Euonymus, Fuchsias, Impatiens, Primulas, Rhododendron, and Sedums. It does not matter whether the plants are inside or out, but they are more likely to attack plants grown in pots or containers, because the soil is usually warmer and protected from frost. All adult vine weevils are female and each can lay hundreds of eggs during the summer. The adults are about 10mm long, dull black beetles, usually with small patches of yellow/orange scales on the wing cases, with a pear-shaped body, the thorax being much smaller, and fused wing covers which are unable to fly, but can crawl anywhere even up the sheer sides of a glass. Adults feed at night eating the leaves of plants leaving irregular semi-circular notches in leaf edges during the summer and larvae feeds underground so they are rarely seen. The adult damage is unsightly, but not fatal to the plant and is an indication that eggs may be found laid in the soil close to the plant. The eggs are brown and are about 1mm in diameter, making them extremely difficult to see in the soil. The larvae hatch and live in the soil until the spring when they pupate to adults. After feeding for 2-3 weeks, the adults begin to lay eggs. Occasionally males are found, but almost all weevils are produced by parthenogenesis. The adults are slow climbers and do not fly. If they are disturbed they play dead and usually fall to the ground. The larvae are stout, curved, creamy white, legless grubs with brown heads and up to 10mm long. The most damage is done by the larvae which feed on the roots of many plants and the tubers of plants. The first sign of the larva presence is usually yellowing of the leaves, poor growth and wilting which does not respond to watering, by which time it is usually too late to save the plant. If it is detected early and the damage is not too great it is possible to save the plant by washing the soil from the plant and repotting.
See these other Weevils Apple Blossom Weevil, Beech Leaf Mining Weevil, Figworth Weevils, Gorse Seed Weevil, Leaf Weevils, Nut Weevil, Pea and Bean Weevil, Turnip Gall Weevil, Weevils, Willow Flea Weevil.


Control

They are difficult to control because of their nocturnal behaviour and the larva lives in the soil. Traps made from corrugated cardboard made into a roll and left for the adults to hide in during the day then examined to destroy any beetles found. On warm spring or summer evenings inspect plants and walls by torchlight and kill the adult weevils. Trap adults with sticky insecticidal tapes placed around pots or on greenhouse staging. These work because the adults have to walk up the plant. Encourage natural enemies. Vine weevils and their grubs are eaten by a variety of predators such as birds, frogs, toads, shrews, hedgehogs, centipede and predatory ground beetles. There are a few nematodes that specifically kill Vine Weevil available from Organic suppliers, but they are temperature dependent needing the temperature to be between 10 to 20 degrees Centigrade. Systemic insecticides can be used to kill the adults before they can start laying eggs. Finally soaking the soil with insecticidal solutions will kill the larvae.
See also these other Eelworms EELWORMS, ENCHYTRAEID WORMS, CHRYSANTHEMUM EELWORM, LEAF AND BUD EELWORM, NARCISSUS EELWORM, ONION EELWORM, PHLOX EELWORM, POTATO CYST EELWORM, CHAFER GRUBS, DIEBACK, IRIS BORER CATERPILLARS, LEATHERJACKETS, LILY VIRUSES, NUT WEEVIL, PEA AND LEAF POD SPOT, ROOT KNOT EELWORMS, SLUGS, SNAILS, STEM AND BULB EELWORM, TOMATO CYST EELWORMS, WILTING, WIREWORM, WORMS.

P_vineweevil1 P_vineweevil2 P_vinwvildamage

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