Black Vine Weevil
Black Vine Weevil, Snout Beetle, Kalander (Afr.), Snuitkewer (Afr.)
A Vine Weevil is a type of beetle that feeds off of a broad range of plants, both indoors and out. However, these beetles have the most substantial impact on container plants. They can be found in spring and summer eating leaves, but during autumn and winter, the grubs cause the most damage by feeding off the roots, which can cause the plant to wilt and possibly die.
Grubs feed off the roots of plants resulting in wilting plant death.
Vine weevil eggs are a source of food for predatory, soil-dwelling insects.
Adults: The adult weevil is a dark black, matte colour and have fused wing covers so are unable to fly. They have six legs and two long antennas on their head. They're nocturnal, so they come out at night to feed on the outer parts of leaves. Larvae: Small, slightly curved and are creamy-white with light brown heads that measure around 10mm in length. They are located on the roots. Pupae: Currently unavailable. Eggs: The eggs are so tiny you need a hand lens to see them.
You may see irregular notches in your leaf margins during the summer months. Small, black beetles on leaves at night. Sudden wilting of plants in autumn and winter. Numerous creamy-white grubs around the roots of plants.
Central Europe, including the UK
Unfortunately, few treatments can eliminate this pest because they burrow within the roots of host plants. It's important to note that Weevils are nocturnal, so you're not going to catch them in the daytime. If you suspect a possible infestation, or, come to find your garden plants have been attacked but there is no sign of any culprit, you may want to attempt a few evening torch checks. Check on and under the leaves and fruits of plants. It's thought that good housekeeping, such as practising: mulching, re-hilling, field sanitation, crop rotation and using clean planting material, can significantly reduce the severity of an infestation. Pheromone traps can be used to monitor pest populations in the garden. Sticky barriers can also be effective in some cases. Likewise, diatomaceous earth dusted over leaves and around the bases of plants can kill Weevils. Be careful during application, as this stuff is nasty if inhaled and can be extremely irritable when in contact with the eyes. Nematodes can be used and introduced to the soils of your plants, and you can buy these from some garden centres or online. You can use them in both containers or open ground. By using nematodes such as Steinernema kraussei, you can help to reduce any grubs that are in the soil. These should be applied from August to early September for the best results, as larvae will be smaller in size and not have caused too much damage already.
Ornamental plants and fruit plants, in particular vines, Primula, Rhododendron, Heuchera, Cyclamen and strawberries.
Place any grubs found on perches for garden birds to feast.